Composition for temporary fixation

Abstract

The present invention provides a means with which it is possible to suppress heat generation associated with light irradiation, and to mix a sufficient amount of a UV absorber while ensuring long-term availability for use for temporary fixation in an electronic device manufacturing process. The present invention relates to a photocurable composition comprising (A) a first (meth)acrylate monomer containing at least a monofunctional (meth)acrylate monomer, (B) a photoradical polymerization initiator, and (C) a UV absorber, the photocurable composition being characterized in that: component (A) includes (A-1) a monofunctional (meth)acrylate monomer and (A-2) a polyfunctional (meth)acrylate monomer; and with respect to the polar term δP at 25 °C in the Hansen solubility parameter, the absolute value of the difference between δP of component (A) and δP of component (C) is at most 5, and with respect to the dispersion term δD at 25 °C in the Hansen solubility parameters, δD of the component (A) is 16 to 20; and the Hansen solubility parameter is calculated by converting the molecular structural formula into SMILES notation in Hansen solubility parameters in practice (HSPiP) software.

Description

[Technical Field]

[0001] This invention relates to a composition for use in temporary fixation. [Background technology]

[0002] In the manufacture of electronic devices, inorganic materials such as silicon are used as substrates. Wafer-type substrates with a thickness of several hundred micrometers are commonly used, obtained by processing the surface of these substrates, such as forming insulating films, creating circuits, and thinning by grinding. However, many substrates are made of brittle and easily broken materials, so measures to prevent damage are necessary, especially during thinning by grinding. Conventionally, this measure involves applying a temporary fixing protective tape, which can be peeled off after the processing is complete, to the side opposite the surface to be ground (also called the back). This tape uses an organic resin film as its base material, and while it is flexible, its strength and heat resistance are insufficient, making it unsuitable for use in processes involving high temperatures.

[0003] Therefore, a system has been proposed that provides sufficient durability to the conditions of processes such as backside grinding and backside electrode formation by bonding an electronic device substrate to a support such as silicon or glass via an adhesive. What is important in this process is the adhesive layer used when bonding the substrate to the support. This adhesive must be able to bond the substrate to the support without any gaps, have sufficient durability to withstand subsequent processes, and finally allow the thinned wafer to be easily peeled off the support, i.e., to be temporarily fixed.

[0004] The processing of such wafers mainly involves spin coating, vacuum bonding and photocuring, thinning by grinding and polishing, high-temperature processing, laser stripping, and removal of temporary fixative.

[0005] In the spin coating process, in order to uniformly form a film of the temporary fixative on the wafer, it is required that the temporary fixative has a suitable viscosity and be a Newtonian fluid (or that its shear viscosity is independent of the shear rate).

[0006] In the vacuum bonding / UV curing step, temporary fixing agents are required to be capable of being cured by irradiation with light such as ultraviolet (UV) light in a short time on a support such as glass, and to generate less outgassing (low outgassing property).

[0007] In the thinning step by grinding / polishing, in order to avoid damage caused by the local load of the grinder applied to the substrate, temporary fixing agents are required to have an appropriate hardness that can disperse the load in the in-plane direction, prevent local subsidence of the substrate and maintain flatness. In addition, adhesiveness to the support, appropriate high elastic modulus for protecting edges, and chemical resistance are also required.

[0008] In the high-temperature treatment step, temporary fixing agents are required to have heat resistance that can withstand long-time high-temperature treatment in vacuum (for example, 1 hour or more at 300°C or higher).

[0009] In the laser lifting-off step, temporary fixing agents are required to be capable of being lifted off at high speed by a laser such as a UV laser.

[0010] In the removal step, in addition to easy peelability that allows the substrate to be easily peeled off from the support, cohesive properties to prevent adhesive residue from remaining on the substrate after peeling and easy cleanability are required.

[0011] In view of such background, for example, Patent Document 1 discloses a temporary fixing composition comprising (A-1) a monofunctional (meth)acrylate in which the side chain is an alkyl group having 18 or more carbon atoms and the Tg of the homopolymer is -100°C to 60°C, (A-2) a polyfunctional (meth)acrylate, (B) a polyisobutene homopolymer and / or a polyisobutene copolymer, and (C) a photoradical polymerization initiator, which is claimed to be excellent in heat resistance, low outgassing property, and peelability.

[0012] Patent Document 2 also discloses a method for producing a laminate including a photothermal conversion layer containing a light absorber such as carbon black and a thermally decomposable resin, which is used for producing a thinned base material. [[PRIOR ART DOCUMENTS]] [[PATENT DOCUMENTS]]

[0013] [Patent Document 1] International Publication No. 2021 / 235406 [Patent Document 2] Japanese Patent Publication No. 2009-155652 [Overview of the Initiative] [Problems that the invention aims to solve]

[0014] Patent Document 1 discloses that UV absorbers can be added. However, in some applications, such as when it is desirable to suppress heat generation associated with light irradiation, it may be necessary to incorporate a relatively large amount of UV absorber. In general, UV absorbers are poorly soluble solids. Patent Document 1 does not mention how compatibility issues with other raw materials are less likely to occur even when the amount of UV absorber is large.

[0015] Furthermore, the method described in Patent Document 2 involves the carbon black in the photothermal conversion layer generating heat, which decomposes the thermally decomposable resin and reduces its peeling force. This inevitably results in a large amount of heat being generated, which has the problem of adversely affecting products that are sensitive to heat.

[0016] This invention has been made in view of the above-mentioned problems, and aims to provide a temporary fixation composition that can incorporate a sufficient amount of UV absorber with long-term availability for temporary fixation applications. [Means for solving the problem]

[0017] To solve the above-mentioned problems, the present invention can provide the following embodiments.

[0018] Appearance 1. (A) The first (meth)acrylate monomer, (B) Photoradical polymerization initiator, (C) UV absorber and A photocurable composition comprising, (A) Component is, (A-1) Monofunctional (meth)acrylate monomers, and (A-2) polyfunctional (meth)acrylate monomer comprising, with respect to the polar term δ of the Hansen solubility parameter at 25°C P , the absolute value of the difference between δ P of component (A) and δ P of component (C) is 5 or less, with respect to the dispersion term δ of the Hansen solubility parameter at 25°C D , δ D of component (A) is 16 or more and 20 or less, wherein said Hansen solubility parameter is calculated by converting and introducing a molecular structural formula in SMILES notation into HSPiP (Hansen Solubility Parameters in Practice) software A composition characterized by the above.

[0019] Aspect 2. The composition according to Aspect 1, wherein the mass ratio of component (A-1) to component (A-2) is in the range of (A-1):(A-2) = 1:5 to 2:1.

[0020] Aspect 3. The composition according to Aspect 1 or 2, wherein the monofunctional (meth)acrylate monomer has an aromatic ring.

[0021] Aspect 4. (D) (meth)acrylate polymer further comprising, with respect to the polar term δ of the Hansen solubility parameter at 25°C P , the absolute value of the difference between δ P of component (D) and δ P of component (C) is 5 or less, with respect to the dispersion term δ of the Hansen solubility parameter at 25°C D , δ D of component (D) is 16 or more and 20 or less The composition according to any one of Aspects 1 to 3, characterized by the above.

[0022] Aspect 5. (E) Second (meth)acrylate monomer It is defined as, The polarity term δ at 25°C among the Hansen solubility parameters P Regarding the δ of component (E), P and the δ of component (C) P The absolute value of the difference is greater than 5, or The dispersion term δ at 25°C among the Hansen solubility parameters D Regarding the δ of component (E), D is less than 16 or more than 20 Regarding component (E), (E) Does not contain component (E), or when the sum of component (A) and component (E) is taken as 100% by mass, component (E) is 50% or less by mass. A composition according to any one of embodiments 1 to 4, characterized by the above.

[0023] Appearance 6. The composition according to any one of embodiments 1 to 5, wherein component (C) has one or more polymerizable functional groups per molecule.

[0024] Appearance 7. The composition according to any one of embodiments 1 to 6, wherein the amount of component (C) is 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the entire composition excluding components (C) and (B).

[0025] Appearance 8. The composition according to embodiment 7, wherein the amount of component (C) is 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the entire composition excluding components (C) and (B).

[0026] Appearance 9. A composition according to any one of embodiments 1 to 8, wherein a composition formulated at 70°C in a light-shielding container does not precipitate when left to stand at 23°C and then stored in a constant temperature bath at 15°C for 3 days.

[0027] Appearance 10. (A) A first (meth)acrylate monomer comprising at least a monofunctional (meth)acrylate monomer, (B) Polymerization initiator and (C) UV absorber and A composition comprising, (A) Component is, (A-1) Monofunctional (meth)acrylate monomer including, A composition characterized by the following features. [Effects of the Invention]

[0028] According to the present invention, the effect is obtained that a sufficient amount of UV absorber can be incorporated with long-term availability in temporary fixation applications. [Modes for carrying out the invention]

[0029] In this specification, unless otherwise specified, numerical ranges include their upper and lower limits. In this specification, a monofunctional (meth)acrylate means a compound having one (meth)acryloyl group in one molecule. A polyfunctional (meth)acrylate means a compound having two or more (meth)acryloyl groups in one molecule. An n-functional (meth)acrylate means a compound having n (meth)acryloyl groups in one molecule. The polymerizable functional group in a polyfunctional (meth)acrylate may have only an acryloyl group, only a methacryloyl group, or both an acryloyl group and a methacryloyl group. 20 " and "C 10 ~C 20 The notation " and so on refers to a hydrocarbon group with 1 to 20 carbon atoms or a hydrocarbon group with 10 to 20 carbon atoms.

[0030] In one embodiment of the present invention, a photocurable composition can be provided that contains (A) a first (meth)acrylate monomer comprising at least a monofunctional (meth)acrylate monomer, (B) a polymerization initiator, preferably a photoradical polymerization initiator, and (C) a UV absorber, and preferably having Hansen solubility parameters that satisfy predetermined conditions. Hereinafter, this photocurable composition may be simply referred to as "composition" or "temporary fixative" in this specification. In another embodiment, a cured product obtained by curing the composition can also be provided, which can be cured with light of a wavelength corresponding to component (B) and / or component (C) (e.g., ultraviolet light).

[0031] The Hansen solubility parameters of this curable composition (i.e., in its liquid, viscous, or varnish-like state before curing) shall be calculated using the HSPiP (Hansen Solubility Parameters in Practice) software, with a measurement temperature of 25°C, by converting and importing the target molecular structure formula using SMILES notation (the same shall apply hereafter unless otherwise specified). The HSPiP software is available from the official website listed below. https: / / www.hansen-solubility.com / downloads.php

[0032] It is well known that the Hansen solubility parameter has the following three components. δ D :Dispersion term (van der Waals force) δ P :Polar term δ H : Hydrogen bond term In this invention, the polar term δ P and the dispersion term δ D By focusing on and controlling this aspect, it becomes possible to ensure sufficient compatibility of component (C).

[0033] In other words, with respect to the Hansen solubility parameter at 25°C (as described below), the δ of component (A) P and the δ of component (C)P The absolute value of the difference is 5 or less, and the δ of component (A) D The ratio must be between 16 and 20. This provides the effect of suppressing the unwanted precipitation of component (C). It is also permissible for this composition to contain multiple types of a certain component. Naturally, in this case, each of those multiple types must satisfy the above conditions regarding the Hansen solubility parameter.

[0034] While we do not wish to be bound by any particular theory, it is presumed that when the molecules of component (C) become more prone to aggregation, precipitation is more likely to occur. For this reason, the inventors have found that component (C) and δ P We realized that by using component (A), which is similar, we could prevent the aggregation of the molecules of component (C). Furthermore, not only that, but the δ of component (A) D By optimizing the (A) components, unwanted interactions between them were also suppressed, thus completing the present invention.

[0035] (A) Component δ P Preferably, the values ​​are 1.5 to 11.5, 2.0 to 11.0, 2.5 to 10.5, and 3.0 to 10.0.

[0036] (A) Component δ H Preferably, the values ​​are 2.5 to 7.5, 3.0 to 7.0, 3.5 to 6.5, and 4.0 to 6.0.

[0037] The (meth)acrylate monomer, which is component (A) of this composition, can be appropriately selected depending on the (C) component used in combination, taking into consideration the Hansen solubility parameter. Component (A) includes at least (A-1) monofunctional (meth)acrylate monomer and (A-2) polyfunctional (meth)acrylate monomer. The mass ratio of component (A-1) to component (A-2) may be in the range of (A-1):(A-2)=1:5 to 2:1, and more preferably in the range of 1:3 to 1.3:1.

[0038] Component (A-1) may include any monofunctional (meth)acrylate monomer, preferably an aromatic monofunctional (meth)acrylate monomer. Examples of aromatic monofunctional (meth)acrylates include C1-C 20 Alkylphenol (meth)acrylate, C1-C 20 Alkylphenol EO (ethylene oxide) modified (meth)acrylate may be included.

[0039] (A-2) Component may include any two- or more (meth)acrylate monomers. Examples of two- or more

[0040] Aromatic difunctional (meth)acrylates can be added to this composition to form a rigid skeleton. The rigidity can be further enhanced if the aromatic difunctional (meth)acrylate has a fused ring skeleton. An example of an aromatic difunctional (meth)acrylate is 9,9-bis[4-(2-hydroxyC1~C 20 Alkoxy)phenyl]ful orange (meth)acrylate, C1-C 20 Alkoxylated bisphenol A di(meth)acrylate, benzyl di(meth)acrylate, 1,3-bis(2-(meth)acryloyloxy C1~C 20 Examples include alkyl)benzene, 2,2-bis(4-(meth)acryloxydiethoxyphenyl)propane, or structural isomers thereof. Preferably, di(meth)acrylates having a fused ring skeleton, such as fluorene, indene, indecene, anthracene, azulene, or triphenylene, may be included.

[0041] Examples of aliphatic difunctional (meth)acrylates include C1-C 20 Examples include alkyldiol di(meth)acrylates. C1~C 20Examples of alkyldiol di(meth)acrylates may include 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, neopentyl glycol-modified trimethylolpropane di(meth)acrylate, stearic acid-modified pentaerythritol di(meth)acrylate, tripropylene glycol di(meth)acrylate, 2,2-bis(4-(meth)acryloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloxytetraethoxyphenyl)propane, isocyanurate ethylene oxide-modified di(meth)acrylate, and caprolactone-modified hydroxypivalate neopentyl glycol di(meth)acrylate.

[0042] Further examples of aliphatic difunctional (meth)acrylates include C1-C 20 Alkoxylated hydrogenated bisphenol A di(meth)acrylate (including alkylene oxide-modified hydrogenated bisphenol A di(meth)acrylate), 1,3-di(meth)acryloyl oxyadamantane, tricyclo C 10 ~C 20 Alkanedimethanol di(meth)acrylate (e.g., tricyclodecanedimethyl di(meth)acrylate), dicycloC5~C 20 Examples include di(meth)acrylates, or structural isomers thereof.

[0043] Examples of trifunctional (meth)acrylates include ethylene oxide-modified isocyanurate tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, and tris[(meth)acryloyloxyethyl]isocyanurate.

[0044] Examples of (meth)acrylates with four or more functions include ditrimethylolpropanetetra(meth)acrylate, dimethylolpropanetetra(meth)acrylate, pentaerythritoltetra(meth)acrylate, pentaerythritolethoxytetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0045] In a more preferred embodiment, a composition can be provided that includes a combination of an aromatic monofunctional (meth)acrylate as component (A-1) and an aromatic difunctional (meth)acrylate as component (A-2). When this combination is included in the composition after adjusting the Hansen solubility parameter considering component (C), an effect is obtained in which the precipitation of component (C) is more easily suppressed.

[0046] The content of component (A) is preferably 45 to 75 parts by mass, 45.0 to 75.0 parts by mass, 47.5 to 72.5 parts by mass, 50 to 70 parts by mass, and 50.0 to 70.0 parts by mass, based on 100 parts by mass of the total amount remaining after removing components (C) and (B) from the entire composition.

[0047] The content of component (A-1) is preferably 2.5 to 35 parts by mass, 2.5 to 35.0 parts by mass, 5 to 30 parts by mass, 5.0 to 30.0 parts by mass, and 7.5 to 27.5 parts by mass, based on 100 parts by mass of the total amount remaining after removing components (C) and (B) from the entire composition.

[0048] The content of component (A-2) is preferably 10 to 60 parts by mass, 10.0 to 60.0 parts by mass, 15 to 55 parts by mass, 15.0 to 55.0 parts by mass, and 17.5 to 52.5 parts by mass, based on the total amount remaining after removing components (C) and (B) from the entire composition, with 100 parts by mass.

[0049] The polymerization initiator, preferably a photoradical polymerization initiator, which is component (B) of this composition, is a substance that can initiate the radical polymerization of component (A) (and other monomers as needed) upon irradiation with light, and is, for example, a compound whose molecule is cleaved and splits into two or more radicals upon irradiation with ultraviolet or visible light (e.g., wavelength 350-700 nm, preferably 365-500 nm, more preferably 385-450 nm). Examples of photoradical polymerization initiators include bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and bis(η 5 Examples include -2,4-cyclopentadiene-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole-1-yl)-phenyl)titanium, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butan-1-one, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-O-benzoyl oxime, and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]ethanone 1-(O-acetyl oxime). Component (B) may contain one or more of these, or a combination of two or more.

[0050] Preferably, component (B) may include an acylphosphine oxide compound. Preferred acylphosphine oxide compounds include bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. As a photoradical polymerization initiator, it is preferable that it is highly sensitive, has photobleaching properties and therefore exhibits excellent deep curing properties, and that the absorption wavelength range for generating radicals extends to a relatively long wavelength range. In the preferred compounds described above, the absorption wavelength range is in the range up to a wavelength of approximately 440 nm, which is a large difference from the absorption wavelength range of the UV absorber used in the UV laser peeling process described later. In other words, the degree of UV curing inhibition by the UV absorber is small, and radical polymerization can be initiated with longer wavelength light. Therefore, even in the presence of a UV absorber, the effect of initiating radical polymerization at a relatively high speed and efficiently and curing can be obtained.

[0051] In a preferred embodiment, the photoradical polymerization initiator can be selected based on its absorbance. Specifically, when dissolved at a concentration of 0.1% by mass in a solvent that does not have a maximum absorption in the 300-500 nm wavelength range (e.g., acetonitrile or toluene), the photoradical polymerization initiator can be selected from one or more compounds that satisfy one or more of the following conditions: an absorbance of 0.5 or more at a wavelength of 365 nm, an absorbance of 0.5 or more at a wavelength of 385 nm, and an absorbance of 0.5 or more at a wavelength of 405 nm. Examples of compounds that satisfy such conditions include 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]ethanone 1-(O-acetyloxime), which has an absorbance of 0.5 or more at a wavelength of 365 nm when dissolved in acetonitrile as a solvent at a concentration of 0.1% by mass; 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-O-benzoyloxime, which has an absorbance of 0.5 or more at wavelengths of 365 nm and 385 nm; and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide, which have an absorbance of 0.5 or more at wavelengths of 365 nm, 385 nm, and 405 nm.

[0052] Furthermore, from the viewpoint of achieving both curability by photoradical polymerization initiators and UV laser peelability, bis(η) having an absorption wavelength region in the range of 400-500 nm is desirable. 5 -2,4-cyclopentadiene-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole-1-yl)-phenyl)titanium can also be used as a photoradical polymerization initiator.

[0053] (B) As the photoradical polymerization initiator, one or more compounds selected from acylphosphine oxide compounds, titanocene compounds, or α-aminoalkylphenone compounds are preferred in terms of reaction rate, heat resistance after curing, low outgassing, and absorption characteristics in a region different from both the wavelength of the UV laser used in the UV laser peeling process described later and the absorption wavelength region of the UV absorber used in the UV laser peeling process. In addition, as a photoradical polymerization initiator for a resin composition used for temporary fixing to prevent damage from bonding the substrate to the support substrate to the heating process, not for the layer corresponding to the UV laser peeling process among the temporary fixing compositions having the structure described later, oxime ester compounds may also be selected in addition to the above.

[0054] Examples of acylphosphine oxide compounds include bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. Among these, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide is particularly preferred.

[0055] Examples of titanocene compounds include bis(η) 5 An example is -2,4-cyclopentadiene-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole-1-yl)-phenyl)titanium.

[0056] Examples of α-aminoalkylphenone compounds include 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one and 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butan-1-one.

[0057] Examples of oxime ester compounds include 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-O-benzoyl oxime and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]ethanone 1-(O-acetyl oxime). Among these, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]ethanone 1-(O-acetyl oxime) is preferred.

[0058] (B) The amount of photoradical polymerization initiator used is preferably 0.01 to 5 parts by mass, and more preferably 0.1 to 1 part by mass, per 100 parts by mass of component (A), in terms of reaction rate, heat resistance after curing, and low outgassing. If component (B) is 0.01 parts by mass or more, sufficient curability can be obtained, and if it is 5 parts by mass or less, the effect of low outgassing and heat resistance is not easily impaired can be obtained.

[0059] (C) The UV absorber component refers to a compound whose molecules are cleaved and decomposed / vaporized by irradiation with ultraviolet or visible light lasers, and which causes the adhesion between the temporary fixative and the support substrate (or support) to be lost when this decomposition / vaporization occurs at the interface between the support substrate (or support) and the temporary fixative, which was maintained until immediately before the peeling process.

[0060] As a UV absorber, one or more compounds selected from benzotriazole compounds and hydroxyphenyltriazine compounds are preferred in terms of the degree of overlap with the UV laser wavelength in the UV absorption wavelength region, UV absorption characteristics at the same wavelength, low outgassing, and heat resistance. Component (C) has a δ relationship with component (A). P The choice can be made after considering the relationship between the two factors.

[0061] (C) component δ P Preferably, the values ​​are 3 to 10, 3.0 to 10.0, 3.5 to 9.5, 4 to 9, and 4.0 to 9.0.

[0062] The amount of UV absorber component (C) is preferably 1 to 20 parts by mass, and more preferably 5 to 20 parts by mass, based on 100 parts by mass of the total composition excluding components (C) and (B). In other words, the present invention allows for the inclusion of a larger amount of UV absorber compared to the prior art. If the amount of component (C) is 1 part by mass or more, a sufficient UV laser peeling speed can be obtained, and if it is 20 parts by mass or less, the effect of low outgassing and heat resistance is less likely to be impaired can be obtained.

[0063] Preferably, the UV absorber may have one or more polymerizable functional groups (such as (meth)acryloyl groups, vinyl ether groups, or ester groups) per molecule. If the UV absorber has a (meth)acryloyl group, that UV absorber will not be treated as part of component (A). Using component (C) having such polymerizable functional groups has the effect of obtaining a more appropriate crosslinked structure.

[0064] Examples of benzotriazole compounds include 2-[2-hydroxy-5-[2-(meth)acryloyloxy)ethyl]phenyl]-2H-benzotriazole, 2,2'-dihydroxy-4,4'-di-2-(meth)acryloyloxyethoxybenzophenone, 2-(2H-benzotriazole-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol, and 2,2'-methylenebis[6-(2H-benzotriazole-2-yl)-4-(1,1 One or more selected from the group consisting of [3,3-tetramethylbutyl)phenol, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, and 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole are particularly preferred in terms of compatibility with resin components, UV absorption properties, low outgassing properties, and heat resistance.

[0065] As hydroxyphenyltriazine compounds, one or more selected from the group consisting of 2-[4-[(2-hydroxy-3-(2'-ethyl)hexyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine, and 2,4,6-tris(2-hydroxy-4-hexyloxy-3-methylphenyl)-1,3,5-triazine are particularly preferred in terms of compatibility with component (A), UV absorption properties, low outgassing, and heat resistance.

[0066] The composition may further include a (meth)acrylate polymer as component (D). P and the δ of component (C) P The absolute value of the difference is 5 or less, and / or the δ of component (D) D It is preferable that the ratio is between 16 and 20. Examples of such (meth)acrylate polymers include (meth)acrylic polymers or (meth)acrylic copolymers having (meth)acryloyl groups in the side chains. Such polymers are available, for example, as the "Art Resin" series from Negami Kogyo Co., Ltd. and the "KANEKA XMAP" series from Kaneka Corporation. Using component (D) makes it easier to adjust the rigidity and flexibility of the crosslinked structure formed when the composition hardens.

[0067] The weight-average molecular weight of component (D) is preferably 5,000 to 200,000. A weight-average molecular weight of 5,000 or more of component (D) allows for an appropriate viscosity when blended with other polymerizable components. A weight-average molecular weight of 10,000 or more of component (D) provides an appropriate thickening effect. From this viewpoint, a weight-average molecular weight of 6,000 or more of component (D) is more preferable, and 7,000 or more is even more preferable. A weight-average molecular weight of 200,000 or less of component (D) provides good spin-coating properties with low shear rate dependence. From this viewpoint, a weight-average molecular weight of 190,000 or less of component (D) is more preferable, 180,000 or less is even more preferable, 150,000 or less is even more preferable, and 100,000 or less is particularly preferable.

[0068] The functional group equivalent of component (D) is preferably 500 to 20000, more preferably 700 to 10000, and most preferably 1000 to 7000.

[0069] If the composition contains component (D), the amount of component (A) may be 50% by mass or more and 95% by mass or less in the mass ratio of component (A) to component (D), preferably 50% by mass or more and 90% by mass or less, and more preferably 50% by mass or more and 85% by mass or less.

[0070] The composition may further include a second (meth)acrylate monomer as component (E), which is different from component (A). P and the δ of component (C) P The absolute value of the difference is greater than 5, or the δ of component (E) D The ratio is less than 16 or greater than 20. In some embodiments, component (E) is not included, or when the total of components (A) and (E) is 100% by mass, component (E) is preferably 50% by mass or less, and more preferably 40% by mass or less. An example of component (E) is a monofunctional alkyl (meth)acrylate, such as isostearyl (meth)acrylate.

[0071] Unlike the aforementioned Patent Document 2, this composition does not require the separate provision of an adhesive layer and a photothermal conversion layer; it can function by forming only one layer. For this reason, it is preferable that this composition does not contain fillers such as carbon black.

[0072] In this specification, the UV transmittance of the cured material is a value obtained by reflectance spectroscopy. Specifically, the transmittance is obtained using a reflectance spectrometer (V-650, manufactured by JASCO Corporation) with a cured material film approximately 50 μm thick, prepared by sandwiching it between sheets of PET resin, under the following conditions.

[0073] Cell length: 10mm Metering mode: T (Transmittance) Measurement range: 450-200nm Data acquisition interval: 1nm UV / vis bandwidth: 2.0nm Response: medium Scanning speed: 40 nm / min Light source switching: 340nm Light source: D2 / WI Filter switching: Step Correction: Baseline

[0074] In this specification, the weight-average molecular weight is a value on a standard polystyrene basis measured by gel permeation chromatography (GPC). Specifically, the weight-average molecular weight is determined under the following conditions, using tetrahydrofuran as the solvent, a GPC system (SC-8010, manufactured by Tosoh Corporation), and a calibration curve created using commercially available standard polystyrene.

[0075] Flow rate: 1.0ml / min Set temperature: 40℃ Column configuration: One 6.0mm ID x 4.0cm column of "TSK guardcolumn MP (xL)" manufactured by Tosoh Corporation, and two 7.8mm ID x 30.0cm columns of "TSK-GELMULTIPOREHXL-M" manufactured by Tosoh Corporation (16,000 theoretical plates), for a total of three columns (32,000 theoretical plates in total). Sample injection volume: 100 μl (sample solution concentration 1 mg / ml) Fluid delivery pressure: 39 kg / cm² 2 Detector: RI detector (differential refractive index detector)

[0076] This composition can be used as a temporary fixing resin composition, a temporary fixing adhesive, an adhesive sheet, or a temporary fixing adhesive for the manufacture of electronic devices. In this specification, temporary fixing compositions, temporary fixing resin compositions, and temporary fixing adhesives may be collectively referred to as temporary fixing agents.

[0077] When using this composition to bond a substrate to be processed with an optically transparent support substrate (or support), the energy amount in visible light or ultraviolet light (wavelength or central wavelength 365-405 nm) should be 1-20000 mJ / cm². 2 It is preferable to irradiate in such a way that the energy amount is 1 mJ / cm². 2 At this level, sufficient adhesion can be achieved, up to 20,000 mJ / cm². 2 The following conditions result in superior productivity, reduced decomposition products from photoradical polymerization initiators, and suppressed outgassing: 1000-10000 mJ / cm². This is optimal in terms of productivity, adhesion, low outgassing, and ease of removal. 2 It is preferable that this be the case.

[0078] The substrates to be bonded by this composition are not particularly limited, but at least one of the substrates is preferably a transparent substrate that transmits light. Examples of transparent substrates include inorganic substrates such as quartz, glass, silica, calcium fluoride, and magnesium fluoride, and organic substrates such as plastics. Among these, inorganic substrates are preferred because they are versatile and provide a great effect. Among inorganic substrates, one or more selected from glass and silica are preferred.

[0079] This composition may be photocurable, and the resulting cured product has excellent heat resistance and release properties. In one embodiment, the cured product of the composition of the present invention exhibits low outgassing even when exposed to high temperatures, making it suitable for bonding, sealing, and coating various optical components, optical devices, and electronic components. The composition of the present invention is suitable for applications requiring a wide range of durability, such as solvent resistance, heat resistance, and adhesiveness, particularly for semiconductor manufacturing process applications.

[0080] The cured product of this composition can be used in processes over a wide temperature range from room temperature to high temperatures. The heating temperature during the process is preferably 350°C or lower, more preferably 300°C or lower, and most preferably 250°C or lower.

[0081] In one embodiment, an adhesive is provided in which a substrate is bonded using the composition as an adhesive. This adhesive can be peeled off by applying an external force. For example, it can be peeled off by inserting a blade, sheet, or wire into the joint. Alternatively, it can be peeled off by scanning a UV laser or IR laser across the entire surface from the optically transparent substrate side of the adhesive.

[0082] In one embodiment, when the composition (in its uncured state) is mixed in a light-shielding container at 70°C, allowed to stand until it reaches 23°C, and then stored in a constant temperature bath at 15°C, it is preferable that precipitation does not occur for 3 days or more, more preferably 4 days or more, even more preferably 7 days or more, and even more preferably 14 days or more. In other words, the composition has properties that make it extremely resistant to precipitation. In another embodiment, a storage method can also be provided in which the composition is mixed in a light-shielding container at 70°C, allowed to stand until it reaches 23°C, and then stored in a constant temperature bath at 15°C without precipitation occurring for 3 days or more (preferably 4 days or more, 7 days or more, or 14 days or more). In other words, the present invention can also provide a method for extending the shelf life of a composition by adjusting the Hansen solubility parameters of each component. [Examples]

[0083] The present invention will be described in more detail below based on examples and comparative examples, but the present invention is not limited thereto.

[0084] Unless otherwise specified, experiments were conducted at a temperature of 25°C and a humidity of 50%. Hansen solubility parameters were calculated using the method described above. Temporary fixation compositions with the compositions shown in the table below (units are parts by mass) were prepared and evaluated. The following compounds were selected as components.

[0085] [Table 1] The unit of quantity used is parts by mass.

[0086] [composition] The following was used as component (A-2): A-BPEF-2: 9,9-Bis[4-(2-hydroxyethoxy)phenyl]ful orange acrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd. as "NK Ester A-BPEF-2") HBPE-4: EO-modified hydrogenated bisphenol A diacrylate (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., "HBPE-4", m+n≈4) A-DOD-N: 1,10-decanediol diacrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd. as "NK Ester A-DOD-N")

[0087] The following was used as component (A-1): M-113: Nonylphenol EO-modified acrylate (Aronix M-113, manufactured by Toagosei Co., Ltd., n≒4)

[0088] The following was used as component (B): I819: Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (BASF "Irgacure 819")

[0089] The following was used as component (C): RUVA-93: 2-[2-hydroxy-5-[2-(methacryloyloxy)ethyl]phenyl]-2H-benzotriazole (RUVA-93, manufactured by Otsuka Chemical Co., Ltd.) P-66: 2,2'-dihydroxy-4,4'-di-2-acryloyloxyethoxybenzophenone (Dainsorb P-66, manufactured by Yamato Kasei Co., Ltd.)

[0090] The following was used as component (D): APB-001: Polybutyl polyfunctional acrylate polymer containing acryloyl groups in its side chains (manufactured by Negami Kogyo Co., Ltd., "APB-001", weight-average molecular weight 72,000, functional group equivalent 1400)

[0091] The following was used as component (E): ISTA: Isostearyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd. as "ISTA")

[0092] [Preparation of liquid samples] The materials listed in Table 1 were heated and mixed at 70°C in a light-shielding container to prepare a homogeneous liquid sample for temporary fixation, which was then allowed to stand until the temperature reached 23°C.

[0093] [Precipitation test] Each of the obtained temporary fixation compositions was stored in a constant temperature bath at 15°C. Precipitation was evaluated by visually checking the container within 5 minutes of removing it from the constant temperature bath. The number of days until precipitation occurred was measured. If storage was possible for 3 days or more without precipitation, it was evaluated as "good," and if precipitation occurred in less time, it was evaluated as "poor."

[0094] Based on the above results, all of the compositions according to the examples of the present invention could be stored for four days or more without precipitation.

[0095] On the other hand, Comparative Examples 1 and 2, which did not contain component (A-1) and did not meet the conditions of the Hansen solubility parameter, were unsuitable because precipitation occurred on the same day or within two days.

[0096] This composition achieves long-term usability even when a sufficient amount of UV absorber is incorporated, and this also has the remarkable effect of suppressing heat generation associated with light irradiation during laser peeling.

Claims

1. (A) A first (meth)acrylate monomer comprising at least a monofunctional (meth)acrylate monomer, (B) Photoradical polymerization initiator, (C) UV absorber and A photocurable composition comprising, (A) Component is (A-1) Monofunctional (meth)acrylate monomers, and (A-2) Polyfunctional (meth)acrylate monomers Includes, After removing components (C) and (B) from the entire composition, the remaining total amount is 100 parts by mass, and the content of component (A) is 45 to 75 parts by mass. After removing components (C) and (B) from the entire composition, the remaining total amount is 100 parts by mass, and the content of component (C) is 1 to 20 parts by mass. The polarity term δ at 25°C among the Hansen solubility parameters P Regarding (A) component δ P and (C) component δ P The absolute value of the difference is 5 or less. The dispersion term δ at 25°C among the Hansen solubility parameters D Regarding (A) component δ D The number is between 16 and 20, The aforementioned Hansen solubility parameters are calculated by converting and importing the molecular structure formula using SMILES notation in the HSPiP (Hansen Solubility Parameters in Practice) software. A composition characterized by the following features.

2. The composition according to claim 1, wherein the mass ratio of component (A-1) to component (A-2) is in the range of (A-1):(A-2) = 1:5 to 2:

1.

3. The composition according to claim 1 or 2, wherein the monofunctional (meth)acrylate monomer has an aromatic ring.

4. (D) Further comprising a (meth)acrylate polymer, The polarity term δ at 25°C among the Hansen solubility parameters P Regarding the δ of component (D), P and (C) component δ P The absolute value of the difference is 5 or less. The dispersion term δ of the Hansen solubility parameter at 25°C D with respect to component (D), the δ D is 16 or more and 20 or less The composition according to claim 1 or 2, characterized in that...

5. (E) Defined as a second (meth)acrylate monomer, The polarity term δ at 25°C among the Hansen solubility parameters P Regarding the δ of component (E), P and (C) component δ P The absolute value of the difference is greater than 5, or The dispersion term δ at 25°C among the Hansen solubility parameters D Regarding the δ of component (E), D is less than 16 or more than 20 Regarding component (E), Either it does not contain component (E), or when the sum of components (A) and (E) is taken as 100% by mass, component (E) accounts for 50% or less by mass. The composition according to claim 1 or 2, characterized in that...

6. The composition according to claim 1 or 2, wherein component (C) has one or more polymerizable functional groups per molecule.

7. The composition according to claim 1 or 2, wherein a composition formulated at 70°C in a light-shielding container does not precipitate when left to stand at 23°C and then stored in a constant temperature bath at 15°C for 3 days.

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