Conveying member

Abstract

This conveying member, which is used when conveying a member being conveyed while adhered to said member being conveyed, includes a substrate and an adhesive layer that is layered on the substrate and that comprises a curable resin composition containing a surfactant.

Description

Transport materials

[0001] The present disclosure relates to a transport member having a pressure-sensitive adhesive layer made of a curable resin composition and a reusable substrate.

[0002] For example, in the manufacturing process of electronic components, a processing sheet is attached to a workpiece (transported member) for the purpose of fixing the workpiece (transported member) during processing, transport, etc. The processing sheet is an adhesive sheet in which an adhesive layer made of a curable resin composition is formed on at least one surface of a base film, and while it can exert high adhesive strength to fix the workpiece, it has the property that when peeled from the workpiece, the adhesive strength is reduced by curing the curable resin composition to increase the elastic modulus of the adhesive layer, thereby allowing for easy peeling.

[0003] Conventional processing sheets are made into an integrated laminated sheet in which the adhesive layer and the resin film used as the substrate are closely adhered to each other in order to prevent the adhesive layer from remaining on the workpiece. Therefore, after all processing steps are completed and the processing sheet is peeled off from the workpiece, it is usually discarded.

[0004] In contrast, Patent Document 1 discloses a double-sided adhesive tape laminated with a first adhesive layer consisting of a low-tack adhesive layer, a substrate film, and a second adhesive layer consisting of a peelable adhesive layer. This double-sided adhesive tape uses two types of adhesive compositions, allowing adhesives suitable for the surfaces of the semiconductor wafer and carrier substrate, which are the workpieces, to be applied, respectively, so that no adhesive residue remains on either side upon peeling. Patent Document 2 also discloses a single-sided adhesive tape that has an adhesive layer and a polyester film used as the substrate.

[0005] JP 2022-097357 A Patent No. 7084535 A

[0006] However, both of the two types of adhesives used in Patent Document 1 adhere strongly to the substrate film between them, making it difficult to reuse the substrate film. Similarly, in the single-sided adhesive tape disclosed in Patent Document 2, the adhesive layer and the polyester film used as the substrate adhere strongly to each other, making it difficult to reuse the substrate film. Therefore, the adhesive tapes of Patent Documents 1 and 2 are also discarded after being peeled from the workpiece.

[0007] The present disclosure has been made in consideration of the above-mentioned problems, and its purpose is to provide a transport member that can be suitably used as a transport member for transporting a transported member, and that, when peeled from the transported member after the transported member has been transported, allows the adhesive layer to be peeled from the transported member and the substrate, thereby enabling the substrate to be reused.

[0008] The present inventors have focused on the composition of the pressure-sensitive adhesive composition and conducted extensive research, and have found that the above-mentioned problems can be solved by using a specific surfactant, thereby completing the present invention.

[0009] That is, the transport member is used when transporting a transported member in a state where it is attached to the transported member, and includes a substrate and an adhesive layer made of a curable resin composition containing a surfactant laminated on the substrate. As a result, when the transported member is transported, the adhesive layer adheres to the transported member and does not accidentally peel off, and on the other hand, when the transported member is peeled off from the transported member after transportation, the adhesive layer can be peeled off from the transported member and the substrate, making it possible to reuse the substrate.

[0010] The surfactant may be a reactive surfactant having one or more radically polymerizable functional groups.

[0011] The pressure-sensitive adhesive layer may be peelable from the substrate by washing with a washing liquid, for example, by washing with a washing liquid having a pH of 4 to 12.

[0012] The curable resin composition may contain at least one of a (meth)acrylic resin, a curable compound having a radically polymerizable unsaturated bond in the molecule, a radical initiator, and a reactive surfactant.

[0013] The pressure-sensitive adhesive layer may be peelable from the transported member, for example, by applying an external stimulus. The type of stimulus is not particularly limited, and any stimulus may be used.

[0014] In this specification, the term "sheet" is not particularly distinguished from "film" or "tape" and is used to include these terms.

[0015] In this specification, "(meth)acrylic" means acrylic or methacrylic, "(meth)acryloyl" means acryloyl or methacryloyl, and "(meth)acrylate" means acrylate or methacrylate.

[0016] As described above, the adhesive layer can be suitably used as a transporting member for transporting a transported member, and when peeling the adhesive layer from the transported member after transporting the transported member, the adhesive layer can be peeled off from the transported member and the substrate, making it possible to reuse the substrate.

[0017] Fig. 1 is an enlarged perspective view of a transport member according to an embodiment of the present invention, and Fig. 2 is a side view illustrating the transport member when in use.

[0018] Hereinafter, embodiments of the present invention will be described in detail. Note that the following description of the preferred embodiments is essentially for illustrative purposes only and is not intended to limit the present invention, its applications, or its uses. Furthermore, the technical scope of the present invention is not limited to the following embodiments, and also includes other embodiments in which a person skilled in the art appropriately substitutes the configuration of the following embodiments.

[0019] FIG. 1 shows a transport member 1 according to an embodiment of the present invention. FIG. 2 is a diagram illustrating the transport member 1 during use. As shown in FIG. 2, the transport member 1 is attached to a transport target member 100 and is used to transport the transport target member 100. Examples of the transport target member 100 include electronic components, optical components, vehicle-mounted components, and various other products. Examples of electronic components include, but are not limited to, circuit boards, processors, memories, storage devices, and display devices, and include various electronic and electrical components. Examples of optical components include, but are not limited to, lenses, prisms, beam splitters, and mirrors, and include various optical components. Examples of vehicle-mounted components include, but are not limited to, display devices, switches, buttons, and processing devices, and include various other components and products.

[0020] When performing some processing, such as processing, during the manufacture of the above-mentioned parts, components, or products, they need to be transported from one location to another. Furthermore, when attaching or assembling the above-mentioned parts, components, or products to another component, they also need to be transported from one location to another. During such transportation, it may be difficult to directly grasp the above-mentioned parts, components, or products. In such cases, the transport member 1 according to the present embodiment can be attached to the above-mentioned parts, components, or products to hold them, and the transport member 1 can be gripped, thereby enabling the above-mentioned parts, components, or products to be transported without directly gripping them. One transported member 100 may be attached to one transport member 1, or multiple transported members 100 may be attached to one transport member 1. Furthermore, one transported member 100 may be attached to multiple transport members 1. Furthermore, the transported member 100 can be attached to the transport member 1 and held thereon during processing, thereby positioning the transported member 100 at a predetermined position.

[0021] The transport member 1 includes a substrate 2 and a pressure-sensitive adhesive layer 3. The substrate 2 may be, for example, a film, tape, sheet, plate, or block. The size of the substrate 2 is not particularly limited and can be set to any size. The thickness of the substrate 2 can be set, for example, in the range of 0.01 mm to 50.0 mm. The length and width of the substrate 2 can each be set, for example, in the range of 1 mm to 10 m. The substrate 2 may be long, having a length of several meters or more, or several tens of meters or more. In this case, it can be cut to a predetermined length before use. The shape of the substrate 2 is not particularly limited and may be, for example, rectangular, circular, elliptical, polygonal, or a free-form curve. The substrate 2 may also have through-holes or slits that penetrate through the thickness direction.

[0022] The pressure-sensitive adhesive layer 3 is laminated on one surface of the base material 2 and is integrated with the base material 2. The thickness of the pressure-sensitive adhesive layer 3 is not particularly limited, but can be set, for example, in the range of 0.01 mm to 10.0 mm. The adhesive strength of the pressure-sensitive adhesive layer 3 can be set by the composition and blending ratio of the pressure-sensitive adhesive composition that constitutes the pressure-sensitive adhesive layer 3, but in this embodiment, the pressure-sensitive adhesive layer 3 is set so that when the transported member 100 is adhered to the pressure-sensitive adhesive layer 3 and the transport member 1 is lifted with the transported member 100 facing downward, the pressure-sensitive adhesive layer 3 does not peel off from the base material 2 and the transported member 100 does not peel off from the pressure-sensitive adhesive layer 3.

[0023] The pressure-sensitive adhesive layer 3 may be laminated over the entire surface of one surface of the substrate 2, or may be laminated over only a portion of one surface of the substrate 2. For example, the pressure-sensitive adhesive layer 3 may be laminated so as to extend linearly on one surface of the substrate 2, or may be laminated in a dotted pattern. When through holes, slits, etc. are formed in the substrate 2, the pressure-sensitive adhesive layer 3 will also have holes in the areas corresponding to the through holes, slits, etc.

[0024] A curable adhesive composition containing a reactive surfactant can be used as the adhesive composition constituting the adhesive layer 3. When the curable adhesive composition contains a reactive surfactant, after all processing steps (treatment steps) on the transported member 100 have been completed and the transported member 100 has been collected, the adhesive layer 3 remaining on the transport member 1 can be washed with a cleaning liquid to reduce the adhesion between the substrate 2 and the adhesive layer 3, and the adhesive layer 3 can be easily peeled off from the substrate 2. This makes it possible to reuse the substrate 2.

[0025] The reactive surfactant may be, for example, a surfactant having one or more radically polymerizable functional groups, such as (meth)acryloyl groups and vinyl groups.

[0026] Examples of reactive surfactants used in this embodiment include anionic reactive surfactants, cationic reactive surfactants, amphoteric reactive surfactants, nonionic surfactants, etc. Only one of the anionic reactive surfactants, cationic reactive surfactants, amphoteric reactive surfactants, and nonionic surfactants may be used as the reactive surfactant, or two or more of the anionic reactive surfactants, cationic reactive surfactants, amphoteric reactive surfactants, and nonionic surfactants may be used as the reactive surfactant.

[0027] The reactive surfactant is not particularly limited, but examples thereof include polyoxyalkylene alkenyl ether ammonium sulfate, bis(polyoxyethylene polycyclic phenyl ether) methacrylate sulfate ester salt, polyoxyethylene styrenated propenyl phenyl ether ammonium sulfate, polyoxyethylene alkylpropenyl phenyl ether sulfate ester ammonium salt, polyoxyalkylene alkenyl ether, polyoxyethylene styrenated propenyl phenyl ether, polyoxyethylene alkylpropenyl phenyl ether, and the like. Only one of these may be used as the reactive surfactant, or two or more of these may be used as the reactive surfactant.

[0028] The content of the reactive surfactant can be from 0.01 to 10 parts by mass, preferably from 0.02 to 5 parts by mass, and more preferably from 0.02 to 3 parts by mass, relative to 100 parts by mass of the (meth)acrylic resin. If the content of the reactive surfactant is too low, the pressure-sensitive adhesive layer 3 tends to be difficult to peel from the substrate 2 during cleaning, while if the content is too high, uneven distribution of the pressure-sensitive adhesive layer 3 on the surface tends to occur, resulting in a decrease in adhesive strength when processing the transported member 100.

[0029] The curable resin composition used in this embodiment has the property of being cured by application of an external stimulus, such as irradiation with light such as active energy rays, heating, electricity (application of voltage, supply of current), generation of a magnetic field, etc.

[0030] The curable resin composition is not particularly limited, but suitable examples include a photocurable resin composition containing a (meth)acrylic resin having a radically polymerizable unsaturated bond in the molecule and a radically polymerizable polyfunctional oligomer or monomer as curing components, and optionally a crosslinking agent and a photopolymerization initiator; and a thermosetting resin composition containing a (meth)acrylic resin having a radically polymerizable unsaturated bond in the molecule and a radically polymerizable polyfunctional oligomer or monomer as curing components, and optionally a crosslinking agent and a thermopolymerization initiator.

[0031] When the adhesive layer 3 containing such a photocurable resin composition or thermosetting resin composition is subjected to a stimulus such as light irradiation or heating, the entire adhesive layer 3 is uniformly and quickly polymerized and crosslinked to form an integrated body, resulting in a significant increase in the elastic modulus due to the polymerization effect and a decrease in adhesive strength.

[0032] The (meth)acrylic resin is a resin obtained by polymerizing a polymerization component containing at least one kind of (meth)acrylic monomer, and examples thereof include (meth)acrylic resins obtained by polymerizing a polymerization component containing a (meth)acrylic monomer as a main component and, in some cases, various other polymerizable monomers. Note that, in this embodiment, the (meth)acrylic resin may be used alone or in combination with two or more kinds of (meth)acrylic resins.

[0033] Incidentally, "containing a (meth)acrylic monomer as a main component" means that the (meth)acrylic monomer accounts for typically 40% by mass or more, preferably 50% by mass or more, and more preferably 60% by mass or more of the total polymerizable components.

[0034] Examples of the (meth)acrylic monomer include (meth)acrylic acid or a derivative thereof, and (meth)acrylamide or a derivative thereof.

[0035] Examples of the derivatives of (meth)acrylic acid include alkyl group-containing (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, 2-methyl-2-nitropropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, t-pentyl (meth)acrylate, 3-pentyl (meth)acrylate, 2,2-dimethylbutyl (meth)acrylate, n-hexyl (meth)acrylate, cetyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 4-methyl-2-propylpentyl (meth)acrylate, and n-octadecyl (meth)acrylate.

[0036] Other examples of the derivatives of (meth)acrylic acid include cycloalkyl (meth)acrylates such as cyclohexyl (meth)acrylate and cyclopentyl (meth)acrylate; aralkyl (meth)acrylates such as benzyl (meth)acrylate; biphenyloxy structure-containing (meth)acrylates such as biphenyloxyethyl (meth)acrylate; 2-isobornyl (meth)acrylate, 2-norbornylmethyl (meth)acrylate, 5-norbornen-2-yl-methyl (meth)acrylate, 3-methyl-2-norbornylmethyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentenyloxyethyl (meth)acrylate. polycyclic (meth)acrylates such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methoxymethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, methoxydiethylene glycol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethyl carbitol (meth)acrylate, phenoxyethyl (meth)acrylate, alkylphenoxypolyethylene glycol (meth)acrylate, and the like; and (meth)acrylates containing an alkoxy group or a phenoxy group, such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methoxymethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, methoxydiethylene glycol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethyl carbitol (meth)acrylate, phenoxyethyl (meth)acrylate, and alkylphenoxypolyethylene glycol (meth)acrylate.

[0037] Further, hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, and 12-hydroxylauryl (meth)acrylate; hydroxyl group-containing (meth)acrylates such as [4-(hydroxymethyl)cyclohexyl]methyl acrylate, cyclohexanedimethanol mono(meth)acrylate, and 2-hydroxy-3-phenoxypropyl (meth)acrylate; epoxy group-containing (meth)acrylates such as glycidyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate glycidyl ether; Examples of the acrylate include halogen-containing (meth)acrylates such as 2,2,2-trifluoroethyl (meth)acrylate, 2,2,2-trifluoroethylethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, hexafluoropropyl (meth)acrylate, octafluoropentyl (meth)acrylate, heptadecafluorodecyl (meth)acrylate, and 3-chloro-2-hydroxypropyl (meth)acrylate; alkylaminoalkyl (meth)acrylates such as dimethylaminoethyl (meth)acrylate; and oxetane group-containing (meth)acrylates such as 3-oxetanylmethyl (meth)acrylate, 3-methyl-oxetanylmethyl (meth)acrylate, 3-ethyl-oxetanylmethyl (meth)acrylate, 3-butyl-oxetanylmethyl (meth)acrylate, and 3-hexyl-oxetanylmethyl (meth)acrylate.

[0038] Examples of the (meth)acrylamide derivatives include N-alkyl group-containing (meth)acrylamide derivatives such as N-methyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-butyl(meth)acrylamide, and N-hexyl(meth)acrylamide; N-hydroxyalkyl group-containing (meth)acrylamide derivatives such as N-methylol(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, and N-methylol-N-propane(meth)acrylamide; aminomethyl(meth)acrylamide; N-aminoalkyl group-containing (meth)acrylamide derivatives such as N-methoxymethyl(meth)acrylamide and N-ethoxymethyl(meth)acrylamide; N-mercaptoalkyl group-containing (meth)acrylamide derivatives such as mercaptomethyl(meth)acrylamide and mercaptoethyl(meth)acrylamide; and heterocycle-containing (meth)acrylamide derivatives such as N-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine, and N-acryloylpyrrolidine.

[0039] These (meth)acrylic monomers may be used singly or in combination of two or more arbitrarily selected types. Among these (meth)acrylic monomers, for example, alkyl group-containing (meth)acrylates are preferably used. The number of carbon atoms in the alkyl group in the alkyl group-containing (meth)acrylates is, for example, 1 to 20, preferably 4 to 18, and more preferably 8 to 12. Among these, n-butyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, and n-lauryl methacrylate are preferred because they have a glass transition temperature (Tg) of −30° C. or less when formed as a homopolymer and are easy to reduce the melt viscosity.

[0040] The polymerization components constituting the (meth)acrylic resin (A) may also contain polymerizable monomers other than (meth)acrylic monomers (hereinafter referred to as "other polymerizable monomers").

[0041] Examples of the other polymerizable monomers include unsaturated carboxylic acids such as crotonic acid, maleic acid, maleic anhydride, fumaric acid, citraconic acid, glutaconic acid, itaconic acid, acrylamido-N-glycolic acid, and cinnamic acid; carboxylic acid vinyl ester monomers such as vinyl acetate, vinyl propionate, vinyl stearate, and vinyl benzoate; aromatic ring-containing monomers such as styrene and α-methylstyrene; acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, alkyl vinyl ethers, vinyl toluene, vinylpyridine, vinylpyrrolidone, itaconic acid dialkyl esters, fumaric acid dialkyl esters, allyl alcohol, acrylic chloride, methyl vinyl ketone, allyl trimethylammonium chloride, and dimethylallyl vinyl ketone. These may be used alone or in combination of two or more arbitrarily selected types.

[0042] The polymerization components constituting the (meth)acrylic resin preferably contain an alkyl group-containing (meth)acrylate and a functional group-containing monomer. The functional group-containing monomer preferably contains at least one functional group-containing monomer selected from a hydroxyl group-containing monomer and a carboxyl group-containing monomer. Of these, a functional group-containing monomer containing a (meth)acryloyl group is preferred. Of these, hydroxyl group-containing (meth)acrylates such as 2-hydroxyethyl (meth)acrylate and (meth)acrylic acid are particularly preferred.

[0043] The content of the alkyl group-containing (meth)acrylate is, for example, 40% by mass or more, preferably 50% by mass or more, and more preferably 60% by mass or more, relative to the total polymerizable components constituting the (meth)acrylic resin, with the upper limit being 100% by mass.

[0044] The content of the functional group-containing monomer is preferably 0.1% by mass or more and 40% by mass or less, more preferably 1% by mass or more and 35% by mass or less, and particularly preferably 5% by mass or more and 30% by mass or less, based on the total polymerizable components constituting the (meth)acrylic resin. If the content of the functional group-containing monomer is too small, the cohesive strength when the pressure-sensitive adhesive layer 3 is formed tends to decrease, and for example, the adhesive performance and releasability before curing by irradiation with active energy rays tend to decrease. Conversely, if the content of the functional group-containing monomer is too large, the melt viscosity tends to increase and the pot life tends to shorten.

[0045] The content of the other polymerizable monomers is from 0% by mass to 30% by mass, and preferably from 0% by mass to 20% by mass, based on the total polymerizable components constituting the (meth)acrylic resin.

[0046] The glass transition temperature (Tg) of the (meth)acrylic resin is preferably 20° C. or lower, more preferably −70° C. to 0° C., particularly preferably −68° C. to −10° C., and even more preferably −65° C. to −30° C. If the glass transition temperature of the (meth)acrylic resin is too low, the cohesive strength of the pressure-sensitive adhesive layer formed tends to decrease, and for example, the adhesive performance and peelability before curing with active energy rays tend to decrease. On the other hand, if the glass transition temperature of the (meth)acrylic resin is too high, the melt viscosity of the active energy ray-curable pressure-sensitive adhesive composition tends to increase, and the coatability tends to decrease.

[0047] The radically polymerizable polyfunctional oligomer or monomer used in this embodiment has a molecular weight of 10,000 or less, preferably 5,000 or less, and has 2 to 20 radically polymerizable unsaturated bonds in the molecule, so that the three-dimensional reticulation of the pressure-sensitive adhesive layer 3 by light irradiation or heating can be efficiently achieved.

[0048] Examples of the polyfunctional oligomer or monomer include bifunctional (meth)acrylates and trifunctional or higher functional (meth)acrylates.

[0049] Examples of bifunctional (meth)acrylates include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene oxide-modified bisphenol A di(meth)acrylate, propylene oxide-modified bisphenol A di(meth)acrylate, cyclohexanedimethanol ... Examples of the diglycidyl acrylate include acrylate, ethoxylated cyclohexanedimethanol di(meth)acrylate, dimethylol dicyclopentane di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, glycerin di(meth)acrylate, pentaerythritol di(meth)acrylate, ethylene glycol diglycidyl ether di(meth)acrylate, diethylene glycol diglycidyl ether di(meth)acrylate, phthalic acid diglycidyl ester di(meth)acrylate, hydroxypivalic acid-modified neopentyl glycol di(meth)acrylate, and isocyanuric acid ethylene oxide-modified diacrylate.

[0050] Examples of trifunctional or higher functional acrylates include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tri(meth)acryloyloxyethoxytrimethylolpropane, glycerin polyglycidyl ether poly(meth)acrylate, isocyanuric acid ethylene oxide modified triacrylate, caprolactone modified dipentaerythritol penta(meth)acrylate, caprylic / capric tri ... Examples of suitable polyfunctional oligomers or monomers include lactone-modified dipentaerythritol hexa(meth)acrylate, caprolactone-modified pentaerythritol tri(meth)acrylate, caprolactone-modified pentaerythritol tetra(meth)acrylate, ethylene oxide-modified dipentaerythritol penta(meth)acrylate, ethylene oxide-modified dipentaerythritol hexa(meth)acrylate, ethylene oxide-modified pentaerythritol tri(meth)acrylate, ethylene oxide-modified pentaerythritol tetra(meth)acrylate, and ethoxylated 15-glycerin triacrylate. These polyfunctional oligomers or monomers may be used alone or in combination of two or more.

[0051] The content of the polyfunctional oligomer or monomer is 10 parts by mass or more and 200 parts by mass or less, preferably 30 parts by mass or more and 150 parts by mass or less, more preferably 50 parts by mass or more and 120 parts by mass or less, relative to 100 parts by mass of the (meth)acrylic resin. If the content of the polyfunctional oligomer or monomer is too low, the releasability after application of an external stimulus such as light irradiation or heating tends to decrease, while if the content is too high, the cohesive force of the pressure-sensitive adhesive layer 3 tends to decrease, and the adhesive properties before and after application of the external stimulus tend to decrease.

[0052] Examples of crosslinking agents used in this embodiment include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, aziridine-based crosslinking agents, oxazoline-based crosslinking agents, melamine-based crosslinking agents, aldehyde-based crosslinking agents, and amine-based crosslinking agents. Among these, isocyanate-based crosslinking agents are preferred in terms of the adhesiveness of the peel-type pressure-sensitive adhesive sheet and reactivity with (meth)acrylic resins. These crosslinking agents can be used alone or in combination of two or more types.

[0053] Examples of the isocyanate crosslinking agent include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, hexamethylene diisocyanate, diphenylmethane-4,4-diisocyanate, isophorone diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, tetramethylxylylene diisocyanate, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, adducts of these polyisocyanate compounds with polyol compounds such as trimethylolpropane, and biuret and isocyanurate forms of these polyisocyanate compounds.

[0054] Among these, in terms of chemical resistance and reactivity with functional groups, an isocyanurate of hexamethylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, an adduct of 2,6-tolylene diisocyanate and trimethylolpropane, an isocyanurate of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, and an adduct of tetramethylxylylene diisocyanate and trimethylolpropane are preferred.

[0055] Examples of the epoxy crosslinking agent include bisphenol A-epichlorohydrin type epoxy resins, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl erythritol, diglycerol polyglycidyl ether, 1,3'-bis(N,N-diglycidylaminomethyl)cyclohexane, and N,N,N',N'-tetraglycidyl-m-xylylenediamine.

[0056] Examples of the aziridine crosslinking agent include tetramethylolmethane-tri-β-aziridinylpropionate, trimethylolpropane-tri-β-aziridinylpropionate, N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), and N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide).

[0057] Examples of the oxazoline-based crosslinking agent include 2,2' bisoxazoline compounds containing aliphatic or aromatic groups such as 1,2-bis(2-oxazoline), 1,2-bis(2-oxazolin-2-yl)ethane, 1,4-bis(2-oxazolin-2-yl)butane, 1,8-bis(2-oxazolin-2-yl)butane, 1,4-bis(2-oxazolin-2-yl)cyclohexane, 1,2-bis(2-oxazolin-2-yl)benzene, and 1,3-bis(2-oxazolin-2-yl)benzene; and polymers of one or more types of addition-polymerizable oxazolines such as 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, and 2-isopropenyl-5-ethyl-2-oxazoline.

[0058] Examples of the melamine-based crosslinking agent include hexamethoxymethylmelamine, hexaethoxymethylmelamine, hexapropoxymethylmelamine, hexaptoxymethylmelamine, hexapentyloxymethylmelamine, hexahexyloxymethylmelamine, and melamine resins.

[0059] Examples of the aldehyde crosslinking agent include glyoxal, malondialdehyde, succindialdehyde, maleic dialdehyde, glutaric dialdehyde, formaldehyde, acetaldehyde, and benzaldehyde.

[0060] Examples of the amine-based crosslinking agent include hexamethylenediamine, triethyldiamine, polyethyleneimine, hexamethylenetetraamine, diethylenetriamine, triethyltetraamine, isophoronediamine, amino resins, and polyamides.

[0061] The content of the crosslinking agent is usually preferably 0.1 to 20 parts by mass, more preferably 0.2 to 15 parts by mass, and particularly preferably 0.3 to 10 parts by mass, relative to 100 parts by mass of the (meth)acrylic resin. If the content of the crosslinking agent is within the above range, the cohesive strength of the pressure-sensitive adhesive layer 3 is further improved, and the adhesive strength before application of an external stimulus such as light irradiation or heating is improved, so that lifting or peeling tends to be less likely to occur between the transported member 100 and the transport member 1 during the processing or transport step.

[0062] The photopolymerization initiator used in this embodiment may be any one that generates radicals by the action of light, and examples thereof include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyl dimethyl ketal, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexyl phenyl ketone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, and 2-methyl-2-morpholino(4 acetophenones such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, and 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone oligomer; benzoins such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, 3,3',4,4' -benzophenones such as tetra(tert-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzophenone, 4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyloxy)ethyl]benzenemethanaminium bromide, and (4-benzoylbenzyl)trimethylammonium chloride; 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro- Thioxanthones such as 4-propoxythioxanthone and 2-(3-dimethylamino-2-hydroxy)-3,4-dimethyl-9H-thioxanthone-9-one mesochloride; and acylphosphine oxides such as 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide.

[0063] Among these, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, etc. are preferred because of their excellent curability. These photopolymerization initiators can be used singly or in combination of two or more.

[0064] Furthermore, as an auxiliary agent for these photopolymerization initiators, for example, triethanolamine, triisopropanolamine, 4,4'-dimethylaminobenzophenone (Michler's ketone), 4,4'-diethylaminobenzophenone, 2-dimethylaminoethylbenzoic acid, ethyl 4-dimethylaminobenzoate, (n-butoxy)ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, etc. can also be used in combination. One of these auxiliary agents can be selected arbitrarily, or two or more can be selected arbitrarily in combination.

[0065] The content of the photopolymerization initiator is preferably 0.1 parts by mass or more and 20 parts by mass or less, more preferably 0.5 parts by mass or more and 15 parts by mass or less, and particularly preferably 1 part by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the polyfunctional oligomer or monomer. If the content of the photopolymerization initiator is within the above range, for example, the peelability and adhesive properties after light irradiation become good. In addition, the contamination resistance of the transported member 100 also tends to be further improved.

[0066] The thermal polymerization initiator used in this embodiment may be any that decomposes upon heating to generate radicals, and examples thereof include dicumyl peroxide, di-t-butyl peroxide, t-butyl peroxybenzoate, t-butyl hydroperoxide, benzoyl peroxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, and paramenthane hydroperoxide. Among these, cumene hydroperoxide, paramenthane hydroperoxide, and di-t-butyl peroxide are preferred because of their high thermal decomposition temperatures. These thermal polymerization initiators may be used singly or in combination of two or more.

[0067] To the curable resin composition, for example, small amounts of known additives such as monofunctional monomers, antistatic agents, surface conditioners, antifoaming agents, antioxidants, plasticizers, fillers, pigments, diluents, antioxidants, UV absorbers, UV stabilizers, etc. may be added within a range that does not impair the effects of this embodiment. These additives may be used alone as one type, or in combination of two or more types.

[0068] The curable resin composition can be prepared by various conventionally known methods, and the manufacturing method is not particularly limited. For example, it can be manufactured by uniformly stirring all raw materials while stirring using a known device such as a propeller stirrer or homodisper. During the manufacturing process, operations such as filtration, centrifugation, and degassing may be performed. During the manufacturing process, means such as heating, cooling, pressurization, decompression, and inert gas substitution may also be employed. These may be used alone or in combination.

[0069] The transport member 1 of this embodiment can be formed by directly applying the adhesive containing the curable resin composition onto the substrate 2 and drying it under appropriate heat treatment conditions, or by applying the adhesive to a release film and then drying it under appropriate heat treatment conditions, and then transferring the applied adhesive onto the substrate 2.

[0070] Suitable heat treatment conditions include, for example, a temperature of typically 80 to 120°C and a time of typically 0.5 to 15 minutes, although these can be changed depending on the raw materials, conditions, etc. Furthermore, for the purpose of stabilizing the adhesive properties, it is also preferable to perform further aging after drying. The aging conditions are typically a temperature of room temperature (e.g., 23°C) to 70°C and a time of typically 1 to 30 days, although these can be changed depending on the raw materials, conditions, etc.

[0071] The coating method is not particularly limited as long as it is a common coating method. Examples include roll coating, die coating, gravure coating, comma coating, bar coating, offset printing, flexographic printing, and screen printing. The pressure-sensitive adhesive containing the curable resin composition can also be coated onto the substrate 2 by a coating method other than those mentioned above.

[0072] The base material 2 is not particularly limited as long as it can withstand the heat treatment conditions and the like when processing the transported member 100 . Examples of the resin include polyester resins such as polyethylene naphthalate, polyethylene terephthalate, polybutylene terephthalate, and polyethylene terephthalate / isophthalate copolymer; polyolefin resins such as polyethylene, polypropylene, and polymethylpentene; polyethylene fluoride resins such as polyvinyl fluoride, polyvinylidene fluoride, and polyethylene fluoride; polyamides such as nylon 6 and nylon 6,6; vinyl polymers such as polyvinyl chloride, polyvinyl chloride / vinyl acetate copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, and vinylon; cellulose resins such as cellulose triacetate and cellophane; acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, and polybutyl acrylate; polystyrene; polycarbonate; polyarylate; and synthetic resin films such as polyimide; and woven fabrics and nonwoven fabrics made of glass, aluminum, copper, iron, paper such as fine paper and glassine paper, glass fiber, natural fiber, synthetic fiber, etc. These substrates can be used as a single layer structure made of only one material that is arbitrarily selected, or as a multi-layer structure made of two or more materials that are arbitrarily selected.Among these, transparent resin and glass are preferred in terms of responding to external stimuli caused by light irradiation.These resins and glass may be colorless and transparent, or colored and transparent.

[0073] The release film may be, for example, any of the various synthetic resin films, papers, woven fabrics, nonwoven fabrics, etc. exemplified as the films constituting the substrate 2, whose surfaces have been subjected to a release treatment.

[0074] The pH of the aqueous solution (cleaning agent) used to clean the transport member 1 of this embodiment may be acidic, neutral, or alkaline, and an aqueous solution with a pH of 4 to 12 is preferred.

[0075] The cleaning method is not particularly limited as long as it is a commonly known method, and examples thereof include immersion cleaning, ultrasonic cleaning, shower cleaning, spray cleaning, jet cleaning, jet cleaning, bubbling cleaning, swing cleaning, barrel cleaning, and brush cleaning.

[0076] When the transport member 1 is used, the adhesive layer 3 exhibits high adhesiveness to the transported member 100 during processing, while when the transported member 100 is collected, an external stimulus is applied to the adhesive layer 3 to harden the adhesive layer 3, thereby reducing the adhesive strength of the adhesive layer 3 and allowing the transported member 100 to be easily peeled off from the transport member 1. Therefore, the transported member 100 after processing can be collected without damaging or contaminating the transported member 100. Furthermore, after all processing steps are completed and the transported member 100 is collected, the adhesion between the substrate 2 and the adhesive layer 3 can be reduced by washing the transport member 1 with a cleaning liquid, allowing only the adhesive layer 3 to be cleanly and easily peeled off from the substrate 2.

[0077] Furthermore, by using the transport member 1 of this embodiment, the glass or transparent resin used as the substrate 2 can be reused, which contributes to reducing waste from the entire manufacturing process.

[0078] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, % means % by mass and parts means parts by mass.

[0079] Example 1 Preparation of Curable Resin Composition In a room shielded from ultraviolet light, 100 parts by mass (35% by mass as solids) of an acrylic resin solvent-based pressure-sensitive adhesive composed of an acrylic acid ester copolymer, 31.5 parts by mass of a hexafunctional acrylic monomer (Light Acrylate DPE-6A), 3.15 parts by mass of a photoinitiator (SPEEDCURETPO), and 1 part by mass of a reactive surfactant (KH-10) were mixed into a stainless steel container, and a solution adjusted using toluene and ethyl acetate to a solids content of 30 to 40% by mass was mixed and stirred until a homogeneous solution was obtained. 2.16 parts by mass (50% by mass as solids) of an isocyanate compound solution was added as a curing agent to this composition, and the mixture was stirred until a homogeneous solution was obtained, thereby preparing a curable resin composition.

[0080] <Preparation of adhesive layer> The above curable resin composition was applied to a release-treated polyethylene terephthalate film having a thickness of 25 μm, and dried at 100° C. for 2 minutes to remove the solvent and simultaneously promote curing of the acrylic resin, thereby obtaining an adhesive layer having a dry film thickness of 25 μm. A release-treated polyethylene terephthalate film having a thickness of 25 μm was attached to the dried surface of the obtained adhesive layer, and then aging was performed at 50° C. for 2 days to obtain a substrate-less double-sided adhesive sheet.

[0081] The adhesive strength and cleanability of the obtained pressure-sensitive adhesive sheets were evaluated by the following methods.

[0082] (Adhesive Strength) A 25 μm thick polyethylene terephthalate film that had been treated for release was peeled from one side of a substrateless double-sided adhesive sheet, and a 50 μm thick polyethylene terephthalate film that had been treated for easy adhesion was attached to prepare a single-sided adhesive sheet for adhesive strength evaluation. This sheet was then cut into a width of 25 mm, adhered to the surface of a glass plate using a pressure roll with a load of 1 kg, and left in a room adjusted to 23 ° C and 65% RH for 1 hour. Then, a test specimen was prepared by irradiating the specimen with 1000 mJ / cm2 of ultraviolet light using a conveyor-type ultraviolet irradiation device (UV-LED, 365 nm). Using this test specimen, the adhesive strength required to peel the specimen at an angle of 180° before and after ultraviolet irradiation was measured in accordance with JIS Z0237 (peel speed 300 mm / min). The measurement results are shown in Table 1. The adhesive strength is measured in mN / 25 mm.

[0083] (Washability) A release-treated 25 μm-thick polyethylene terephthalate film was peeled off from one side of a substrate-less double-sided adhesive sheet, and an untreated 50 μm-thick polyethylene terephthalate film (assuming the laminated film to be the transported member 100) was attached to the sheet to prepare a single-sided adhesive tape for evaluating washability. This sheet was cut into a width of 25 mm, and then adhered to the surface of a glass plate using a pressure roll with a load of 1 kg. The sheet was then left in a room adjusted to 23°C and 65% RH for 1 hour, and then irradiated with 1000 mJ / cm using a conveyor-type ultraviolet irradiation device (UV-LED, 365 nm). ２ The test piece was then subjected to ultraviolet irradiation. Subsequently, an untreated polyethylene terephthalate film having a thickness of 50 μm was peeled off from the adhesive layer, and the adhesive layer was left on the surface of the glass plate, thereby preparing a test piece. The test piece was immersed in a cleaning solution at room temperature (23±1° C.), and the time (h) required for the adhesive layer remaining on the surface of the glass plate to be washed and peeled off was measured. The cleanability is shown in Table 1, where, when the test piece was lifted out of the cleaning solution, the adhesive layer was naturally peeled off as ◯, the adhesive layer was not peeled off as ×, and the adhesive layer was partially peeled off as △.

[0084] <Preparation of Transport Member> A 25 μm thick polyethylene terephthalate film that had been subjected to a release treatment was peeled off from one side of the above-mentioned substrate-less double-sided adhesive sheet, and the film was attached to a carrier glass substrate 2, thereby preparing a transport member 1.

[0085] A substrate-less double-sided PSA sheet was obtained by preparing a curable resin composition in the same manner as in Example 1, except that the amount of reactive surfactant added was changed to 2 parts by mass. The adhesive strength and cleanability of the obtained PSA sheet were evaluated in the same manner as in Example 1.

[0086] A substrate-less double-sided PSA sheet was obtained by preparing a curable resin composition in the same manner as in Example 1, except that the amount of reactive surfactant added was changed to 3 parts by mass. The adhesive strength and cleanability of the obtained PSA sheet were evaluated in the same manner as in the examples.

[0087] (Example 4) A substrate-less double-sided PSA sheet was obtained by preparing a curable resin composition in the same manner as in Example 1, except that the amount of reactive surfactant added was changed to 5 parts by mass. The adhesive strength and cleanability of the obtained PSA sheet were evaluated in the same manner as in the examples.

[0088] Comparative Example 1 A substrate-less double-sided PSA sheet was obtained by preparing a curable resin composition in the same manner as in Example 1, except that no reactive surfactant was added. The adhesive strength and cleanability of the obtained PSA sheet were evaluated in the same manner as in the example.

[0089]

[0090] Example 5 A test specimen for evaluating cleanability was prepared in the same manner as in Example 1 using the substrate-less double-sided PSA sheet obtained. This test specimen was placed in a glass container and immersed in distilled water at room temperature (23±1°C), after which cleaning was carried out using ultrasonic vibrations (40 kHz, 110 W). As a result, it was confirmed that the PSA layer remaining on the surface of the glass plate peeled off naturally within 3 to 5 minutes.

[0091] The use of the transport member according to the present disclosure is not particularly limited, and it can be suitably used, for example, in the manufacturing processes of electronic components, optical materials, automotive materials, and the like.

[0092] REFERENCE SIGNS LIST 1 Conveying member 2 Substrate 3 Pressure-sensitive adhesive layer 100 Conveyed member

Claims

1. A transport member used when transporting a transported member in a state where it is attached to the transported member, the transport member having a substrate and a pressure-sensitive adhesive layer made of a curable resin composition containing a surfactant laminated on the substrate.

2. The delivery member according to claim 1, wherein the surfactant is a reactive surfactant having one or more radically polymerizable functional groups.

3. The transport member according to claim 1, wherein the adhesive layer can be peeled off from the substrate by washing with a washing liquid.

4. The transportation member according to claim 3, wherein the adhesive layer can be peeled off from the substrate by washing with a washing solution having a pH of 4 to 12.

5. The transport member according to claim 1, wherein the curable resin composition contains at least one of a (meth)acrylic resin, a curable compound having a radically polymerizable unsaturated bond in the molecule, a radical initiator, and a reactive surfactant.

6. The transport member according to any one of claims 1 to 5, wherein the adhesive layer is peelable from the transported member by application of an external stimulus.

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