Adhesive tape

Abstract

The utility model provides an adhesive tape, which can easily identify whether the adhesive tape is a specific adhesive tape. The pressure-sensitive adhesive tape is characterized by having a base material and a pressure-sensitive adhesive layer provided on at least one of the base materials, and having an ink image on the surface of the base material.

Description

Technical Field

[0001] This utility model relates to adhesive tape and its manufacturing method. Background Technology

[0002] Adhesive tape is widely used to fasten components that make up electronic devices and other items together.

[0003] Patent document 1 describes an adhesive tape that has good adhesion and conformability to the adhered object, as well as excellent reprocessing suitability and re-peelability.

[0004] The adhesive tape undergoes several processes before being applied to the component.

[0005] For example, if an electronics manufacturer or similar entity determines the type and shape of the adhesive tape to be used, a die-cutting manufacturer or similar entity will die-cut the determined type of adhesive tape into a specific shape to produce a die-cut product. This die-cut product is then attached to components at the electronics manufacturer or similar entity.

[0006] In adhesive tapes, a release liner is laminated to protect the adhesive layer. This release liner is often printed with the tape manufacturer's logo, etc., and the type of adhesive tape can be identified by the release liner with the logo.

[0007] However, in the processing of adhesive tape, for example, to facilitate die-cutting, sometimes a different release liner is used instead of the original. In such cases, it becomes impossible to determine whether the die-cut product is using the specific adhesive tape not specified by the electronics manufacturer. Consequently, problems repeatedly occur where the adhesive tape is assembled into electronic devices without realizing it is not the correct type, resulting in defects such as peeling due to insufficient adhesive performance.

[0008] Therefore, there is no adhesive tape or its manufacturing method that can be easily identified as a specific adhesive tape, and there is a strong demand for such an adhesive tape to be provided as soon as possible.

[0009] Existing technical documents

[0010] Patent documents

[0011] Patent Document 1: Japanese Patent Application Publication No. 2010-260880 Utility Model Content

[0012] The problem to be solved by the utility model

[0013] The objective of this invention is to solve the aforementioned problems and achieve the following objective: to provide an adhesive tape and its manufacturing method, which allows for easy identification of a specific adhesive tape.

[0014] Methods for solving problems

[0015] In order to achieve the above objectives, the inventors of this utility model have conducted repeated and in-depth research, and as a result, discovered an adhesive tape that can be easily identified as a specific adhesive tape and a method for manufacturing the same.

[0016] This utility model is a utility model developed by the inventor based on the aforementioned technical concept, and is used as a means to solve the above-mentioned problems, as described below. That is,

[0017] <1> An adhesive tape, characterized in that,

[0018] It has a substrate and an adhesive layer disposed on at least one of the substrates.

[0019] The surface of the aforementioned substrate has an ink image.

[0020] <2> A method for manufacturing an adhesive tape, characterized in that it comprises a step of laminating an adhesive layer on at least one side of a substrate, wherein the surface of the substrate has an ink image.

[0021] Utility Model Effect

[0022] According to this invention, an adhesive tape that can be easily identified as a specific adhesive tape and a method for manufacturing the same can be provided. Attached Figure Description

[0023] Figure 1 This is a schematic cross-sectional view of an adhesive tape based on one embodiment of the present invention.

[0024] Figure 2 This is a schematic cross-sectional view of the adhesive tape manufactured in Comparative Example 1.

[0025] Figure 3A This is a diagram showing an example of an ink image.

[0026] Figure 3B yes Figure 3A A magnified view of a portion of the image.

[0027] Figure 4 This is a diagram illustrating the evaluation method for the ease of observation of the ink image of this utility model.

[0028] Figure 5A This is a diagram illustrating the method for measuring the strength of indented adhesive (a diagram showing adhesive tape being attached to an acrylic sheet).

[0029] Figure 5B This is a diagram illustrating the method for determining the strength of indented bonds (showing...) Figure 5A (Image: Acrylic sheet with adhesive tape attached to SUS board).

[0030] Figure 5C This is a diagram illustrating the method for determining the indentation bond strength (showing a method for determining the indentation bond strength of adhesive tape using a tensile testing machine).

[0031] Figure 6A This is a diagram illustrating the method for measuring drop impact (a schematic diagram of the test piece viewed from the top surface).

[0032] Figure 6B This is a diagram illustrating the method for measuring drop impact (a schematic diagram showing the state of the test piece after it has been attached to the acrylic plate, viewed from the top surface).

[0033] Figure 6C This is a diagram illustrating the method for determining drop impact resistance (showing a schematic diagram of the test method for impact resistance testing). Detailed Implementation

[0034] (Adhesive tape)

[0035] The aforementioned adhesive tape comprises a substrate and an adhesive layer, and may further comprise other layers.

[0036] The adhesive layer may be disposed on at least one side of the substrate, or on both sides of the substrate.

[0037] As an example of the adhesive tape of this utility model, for example... Figure 1 As shown, examples include adhesive tape (10) which is formed by laminating adhesive layers (3, 4) on both sides of a substrate (2) and has an ink image (6) on the surface of the substrate (2).

[0038] A release layer (5) may be laminated on the adhesive tape (10).

[0039] <Substrate>

[0040] The aforementioned substrate can support the aforementioned adhesive layer.

[0041] There are no particular restrictions on the above-mentioned substrates; they can be selected appropriately according to the purpose, with resin-made films being preferred.

[0042] There are no particular limitations on the resins mentioned above; they can be appropriately selected according to the purpose. Examples include polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); amide resins such as polyamides (nylon) and fully aromatic polyamides (aromatic polyamides); polyacrylate resins such as polybutyl acrylate and polyethyl acrylate; methacrylate resins such as methyl methacrylate (PMMA); polystyrene; and acrylonitrile-styrene copolymer (AS resin). This includes styrene-based resins such as acrylonitrile-butadiene-styrene copolymer (ABS resin), polyetheretherketone (PEEK), polyetherketoneketone (PEK) and other polyetherketones, polyethersulfone (PES), polysulfone, polyvinyl chloride (PVC), polyphenylene sulfide (PPS), polyimide (PI), polyamide-imide, polyetherimide (PEI), polyesterimide, polycarbonate (PC), polyacetal, polyaryl ethers (polyphenylene ether, etc.), polyphenylene sulfide, polyarylate, polyaryl, polyurethane resins, epoxy resins, and polyolefin resins. These resins can be used individually or in combination.

[0043] There are no particular restrictions on the above-mentioned substrates, and they can be selected appropriately according to the purpose, with foamed materials (foamed material substrates) being preferred.

[0044] There are no particular limitations on the foaming materials mentioned above, and they can be appropriately selected according to the purpose. For example, examples include polyolefin foaming materials composed of polyethylene, polypropylene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, etc., polyurethane foaming materials, and rubber foaming materials composed of acrylic rubber, other elastomers, etc.

[0045] Among these, polyolefin-based foams are preferred.

[0046] There are no particular limitations on the above-mentioned polyolefin foam, and it can be appropriately selected according to the purpose. For example, the following can be used to obtain a cross-linked polyolefin resin foam: a polyolefin resin and a thermally decomposable foaming agent are fed into an extruder, melt-mixed, extruded into sheets from the extruder, and the foamed polyolefin resin sheets formed therefrom are cross-linked by electron beams. Then, foaming, stretching, and thinning are performed to obtain the cross-linked polyolefin resin foam.

[0047] The aforementioned polyolefin resin can be any known material, preferably a polyethylene resin containing 40% by mass or more of a metallocene compound comprising a tetravalent transition metal. Alternatively, the foamed sheet can be sliced ​​in the thickness direction after foaming, and then stretched and skinned using hot rollers to achieve the desired texture.

[0048] In the aforementioned substrate, plasticizers, softeners, antioxidants, flame retardants, fillers such as glass and plastic fibers / hollow spheres / beads / metal powders, colorants such as pigments / dyes, leveling agents, thickeners, waterproofing agents, defoamers, and other known additives can be added to the resin as needed.

[0049] There is no particular limitation on the average thickness of the above-mentioned substrate, which can be appropriately selected according to the purpose. It is preferably 50 μm or more and 1200 μm or less, more preferably 50 μm or more and 500 μm or less, and even more preferably 70 μm or more and 400 μm or less.

[0050] The aforementioned substrates can be commercially available products.

[0051] Commercially available products that serve as the aforementioned base material include, for example, the Volara XL-H series of polyethylene foam manufactured by Sekisui Chemicals Co., Ltd., and the polyolefin series manufactured by Hubei Xiangyuan New Material Technology Co., Ltd.

[0052] There is no particular limitation on the light transmittance of the aforementioned substrate, and it can be appropriately selected according to the purpose. From the perspective of being able to easily identify it as a specific adhesive tape, it is preferably 10% or less, more preferably 1% or less, and even more preferably 0.1% or less.

[0053] There are no particular limitations on the color of the aforementioned substrate, and it can be appropriately selected according to the purpose. Black is preferred from the perspective of being easily identifiable as a specific adhesive tape.

[0054] The aforementioned substrate has an ink image on its surface.

[0055] The ink images mentioned above may contain colorants, resins, etc.

[0056] There are no particular restrictions on the surface of the aforementioned substrate, and it can be appropriately selected according to the purpose.

[0057] When the adhesive layer is provided on one surface of the substrate, for example, the surface of the substrate on the side where the adhesive layer is provided can be taken as an example.

[0058] When the adhesive layer is provided on both surfaces of the substrate, for example, the surface of the substrate on the side where the adhesive layer is provided can be cited.

[0059] The ink image is preferably formed on the surface of the substrate in the form of a printed layer using printing methods such as gravure printing or flexographic printing.

[0060] There are no particular limitations on the color of the ink image (the color of the pigments or other colorants contained in the ink image), and it can be appropriately selected according to the purpose. From the perspective of being easily identifiable as a specific adhesive tape, gold or silver is preferred.

[0061] There are no particular limitations on the resins included in the ink images described above. They can be selected appropriately according to the purpose. Examples include acrylic resins, urethane resins, and polyester resins.

[0062] Among these, acrylic resins are preferred in terms of drop impact resistance.

[0063] The ink used to form the above-described ink image can be any known ink. The ink may contain at least a binder resin (A) and a colorant (B).

[0064] There are no particular limitations on the adhesive resin (A) mentioned above, and it can be appropriately selected according to the purpose. Examples include acrylic resins, urethane resins, polyester resins, polyamide resins, cellulose resins, and vinyl chloride resins. They can be used alone or in combination.

[0065] Among these, from the perspective of not easily reducing the adhesiveness / impact resistance of the tape, the main component of the above-mentioned adhesive resin (A) is preferably an acrylic resin.

[0066] As for the aforementioned acrylic resin, there is no particular limitation as long as it is a resin copolymerized from polymeric monomers with (meth)acrylate as the main component.

[0067] Examples of polymerizable monomers include methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, lauryl methacrylate, stearyl methacrylate, isononyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, and phenoxyethyl methacrylate. The polymerization method is not particularly limited, and substances obtained by known bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, etc., can be used.

[0068] The weight-average molecular weight of the aforementioned acrylic resin is preferably 5,000 or more and 200,000 or less, more preferably 10,000 or more and 100,000 or less.

[0069] The amount of acrylic resin added is preferably 0.1% by mass or more and 80% by mass or less, more preferably 1.0% by mass or more and 50% by mass or less, relative to the total amount of ink solids.

[0070] There are no particular limitations on the polyester resins mentioned above, as long as they are polyester resins produced by reacting alcohols and carboxylic acids using a known esterification polymerization reaction.

[0071] Examples of the aforementioned alcohols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,2-pentanediol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butenediol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerol, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaerythritol, 1,4-cyclohexanediol, 1,2-cyclohexanediol, 1,4-cyclohexanediethanol, 1,2-cyclohexanediethanol, spirocyclodiol, isosorbide diol, etc. They can be used alone or in combination of two or more. Among these, polyfunctional alcohols are preferred.

[0072] Examples of the aforementioned carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, heptanoic acid, caproic acid, octanoic acid, nonanoic acid, decanoic acid, oleic acid, linoleic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, octanoic acid, azelaic acid, sebacic acid, phthalic acid, and 1,4-cyclohexanedicarboxylic acid. They can be used alone or in combination. Among these, polyfunctional carboxylic acids are preferred.

[0073] The weight-average molecular weight of the aforementioned polyester resin is preferably 500 or more and 6000 or less, more preferably 1400 or more and 5500 or less.

[0074] The amount of polyester resin added is preferably 0.1% by mass or more and 80% by mass or less, more preferably 1.0% by mass or more and 50% by mass or less, relative to the total amount of ink solids.

[0075] There are no particular limitations on the polyurethane resins mentioned above, as long as they are polyurethane resins obtained by reacting polyols with polyisocyanates.

[0076] As the aforementioned polyols, various well-known polyols commonly used in the manufacture of polyurethane resins can be used, including ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentylene glycol, 3-methyl-1,5-pentylene glycol, hexanediol, octanediol, 1,4-butynediol, 1,4-butenylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerol, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaerythritol, and other saturated or unsaturated low-molecular-weight polyols, as well as polyalkylene glycols such as polyethylene glycol and polypropylene glycol. The aforementioned polyols can be used alone or in combination of two or more.

[0077] In addition to the above, other examples of polyols include polyester polyols obtained by dehydrating and condensing or polymerizing the aforementioned low-molecular-weight polyols with polycarboxylic acids or their anhydrides, such as sebacic acid, adipic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimecrolic acid, octanoic acid, azelaic acid, trimellitic acid, and pyromellitic acid; and ring-opening polymerization of cyclic ester compounds, such as polycaprolactone, polyvalerol, and poly(β-methyl-γ-valerol). Polyester polyols obtained therefrom; polycarbonate polyols obtained by reacting the aforementioned low-molecular-weight polyols with, for example, dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene, etc.; polybutadiene diols; diols obtained by adding ethylene oxide or propylene oxide to bisphenol A; acrylic polyols obtained by copolymerizing hydroxypropyl acrylate, hydroxybutyl acrylate, etc., or their corresponding methacrylic acid derivatives, with, for example, acrylic acid, methacrylic acid, or their esters, etc., in which one or more hydroxyethyl groups are present in one molecule.

[0078] Examples of polyisocyanates include various well-known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates commonly used in the manufacture of polyurethane resins. For instance, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 1-methyl-2,4-phenylene diisocyanate, 1-methyl-2,6-phenylene diisocyanate, 1-methyl-2,5-phenylene diisocyanate, 1-methyl-2,6-phenylene diisocyanate, 1-methyl-3,5-phenylene diisocyanate, 1-ethyl-2,4-phenylene diisocyanate, 1-isopropyl-2,4-phenylene diisocyanate, 1,3-dimethyl-2,4-phenylene diisocyanate, and 1,3-dimethyl-4,6-phenylene diisocyanate can be used. Isocyanates, 1,4-dimethyl-2,5-phenylene diisocyanate, diethylphenylene diisocyanate, diisopropylphenylene diisocyanate, 1-methyl-3,5-diethylphenylene diisocyanate, 3-methyl-1,5-diethylphenyl-2,4-diisocyanate, 1,3,5-triethylphenyl-2,4-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, 1-methyl-naphthalene-1,5-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7-diisocyanate, 1,1-di... Aromatic polyisocyanates such as naphthyl-2,2'-diisocyanate, biphenyl-2,4'-diisocyanate, biphenyl-4,4'-diisocyanate, 3-3'-dimethylbiphenyl-4,4'-diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, and diphenylmethane-2,4-diisocyanate; tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethyl diisocyanate, trimethylhexamethylene diisocyanate, and 1,3-cyclopentyl diisocyanate. Isocyanates, 1,3-cyclohexyl diisocyanate, 1,4-cyclohexyl diisocyanate, 1,3-di(isocyanate methyl)cyclohexane, 1,4-di(isocyanate methyl)cyclohexane, lysine diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 2,4'-dicyclohexylmethane diisocyanate, 2,2'-dicyclohexylmethane diisocyanate, 3,3'-dimethyl-4,4'-dicyclohexylmethane diisocyanate, and other aliphatic or alicyclic polyisocyanates. These polyisocyanates can be used alone or in combination of two or more.

[0079] Chain extenders can also be used.

[0080] As chain extenders, examples include ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, and amines containing hydroxyl groups in their molecules, such as 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine, and di-2-hydroxypropylethylenediamine. These chain extenders can be used alone or in combination.

[0081] Alternatively, monovalent active hydrogen compounds can be used as capping agents to stop the reaction. Examples of such compounds include dialkylamines such as di-n-butylamine, and alcohols such as ethanol and isopropanol. Furthermore, amino acids such as glycine and L-alanine can be used as reaction terminators, especially when it is desired to introduce carboxyl groups into polyurethane resins. These capping agents can be used alone or in combination.

[0082] Among them, the urethane resin is preferably a urethane resin obtained by reacting the above-mentioned low molecular weight polyol, the above-mentioned polyether polyol and the above-mentioned isocyanate.

[0083] The weight-average molecular weight of the above-mentioned urethane resin is preferably 10,000 or more and 100,000 or less, more preferably 15,000 or more and 80,000 or less.

[0084] The amount of the urethane resin added is preferably 0.1% by mass or more and 80% by mass or less, more preferably 1.0% by mass or more and 50% by mass or less, relative to the total amount of ink solids.

[0085] Examples of the aforementioned polyamide resins include thermoplastic polyamides soluble in organic solvents, which are obtained by polycondensation of polybasic acids and polyamines. Particularly preferred are polyamide resins containing a reaction product of an acid component comprising polymeric fatty acids and / or dimer acids with aliphatic and / or aromatic polyamines; more preferably are substances containing a portion of primary and secondary monoamines.

[0086] Examples of polybasic acids used as raw materials in the aforementioned polyamide resins include, but are not limited to, adipic acid, sebacic acid, azelaic acid, phthalic anhydride, isophthalic acid, octanoic acid, glutaric acid, fumaric acid, pimelic acid, oxalic acid, malonic acid, succinic acid, maleic acid, terephthalic acid, 1,4-cyclohexyldicarboxylic acid, trimellitic acid, dimer acids, hydrogenated dimer acids, and polymeric fatty acids. Among these, polyamide resins containing a structure derived from dimer acids or polymeric fatty acids as a main component (50% by mass or more in the polyamide resin) are preferred. Here, polymeric fatty acids are substances obtained through cyclization reactions of unsaturated fatty acids, including monobasic fatty acids, dimerized polymeric fatty acids (dibasic acids), trimerized polymeric fatty acids, etc. It should be noted that the fatty acids constituting dimer acids or polymeric fatty acids can be appropriately derived from natural oil sources such as tall oil, rice bran oil, palm oil, coconut oil, and soybean oil, and are preferably obtained from oleic acid and linoleic acid.

[0087] Monocarboxylic acids can also be used in combination with polycarboxylic acids. Examples of monocarboxylic acids that can be used in combination include acetic acid, propionic acid, lauric acid, palmitic acid, benzoic acid, and cyclohexanecarboxylic acid.

[0088] Examples of polyamines include polyamines, primary monoamines, and secondary monoamines. Examples of polyamines used in polyamide resins include aliphatic diamines such as ethylenediamine, propylenediamine, hexamethylenediamine, and methylaminopropylamine, as well as aliphatic polyamines such as diethylenetriamine and triethylenetetramine. Examples of alicyclic polyamines include cyclohexylenediamine and isophoronediamine. Furthermore, examples of aromatic aliphatic polyamines include phenylenediamine, and examples of aromatic polyamines include phenylenediamine and diaminodiphenylmethane. Additionally, examples of primary and secondary monoamines include n-butylamine, octylamine, diethylamine, monoethanolamine, monopropanolamine, diethanolamine, and dipropanolamine.

[0089] Among these, polyamide resins that use rice bran fatty acids derived from rice bran oil as reactants are preferred. Furthermore, when using rice bran fatty acids as reactants, aliphatic diamines or alicyclic polyamines are preferably used among the aforementioned polyamines.

[0090] The number average molecular weight of the polyamide resin is preferably 1,000 or more and 30,000 or less, more preferably 1,000 or more and 20,000 or less.

[0091] The acid value of the polyamide resin is not particularly limited, but is preferably 15 mg KOH / g or less.

[0092] The amine value of the polyamide resin is not particularly limited, but is preferably 10 mg KOH / g or less.

[0093] The softening point of the polyamide resin is not particularly limited, but is preferably 90°C or higher and 150°C or lower, more preferably 90°C or higher and 120°C or lower.

[0094] The amount of the polyamide resin used in the mixture is preferably 1% or more and 90% or less by mass relative to the total amount of ink solids, and more preferably 15% or more and 80% or less by mass.

[0095] Examples of cellulose-based resins include cellulose acetate-propionic acid, cellulose acetate-butyrate, cellulose ester resins, cellulose nitrate (also known as nitrocellulose), hydroxyalkyl cellulose, carboxyalkyl cellulose, and other cellulose ester resins.

[0096] The cellulose ester resins described above preferably have an alkyl group, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, etc., and the alkyl group may further have substituents.

[0097] As the aforementioned cellulose-based resin, cellulose acetate-propionate, cellulose acetate-butyrate, or cellulose nitrate are preferred, with cellulose nitrate being particularly preferred.

[0098] The weight-average molecular weight of the cellulose-based resin is preferably 5,000 or more and 200,000 or less, more preferably 10,000 or more and 50,000 or less. Furthermore, the glass transition temperature of the cellulose-based resin is preferably 120°C or more and 180°C or less.

[0099] As the aforementioned nitrocellulose (nitrocellulose), it is preferable to react natural cellulose with nitric acid to replace the three hydroxyl groups in the six-membered ring of the anhydrous pyranose group in the natural cellulose with nitric acid groups, thereby obtaining a substance in the form of a nitrate ester.

[0100] As for the aforementioned nitrocellulose (nitrocellulose), it is preferable to have a nitrogen content of 10% by mass or more and 13% by mass or less, and an average degree of polymerization of 30% by mass or more and 500% by mass or less, and more preferably a nitrogen content of 10% by mass or more and 13% by mass or less, and an average degree of polymerization of 45% by mass or more and 290% by mass or less.

[0101] The amount of nitrocellulose (nitrocellulose) added is preferably 0.15% by mass or more and 40% by mass or less, more preferably 1.0% by mass or more and 35% by mass or less, relative to the total amount of ink solids.

[0102] There are no particular limitations on the above-mentioned vinyl chloride-based resins, as long as they are substances copolymerized from vinyl chloride and vinyl acetate.

[0103] The weight-average molecular weight of the aforementioned vinyl chloride-based resin is preferably 5,000 or more and 100,000 or less, more preferably 10,000 or more and 70,000 or less.

[0104] In the above-mentioned vinyl chloride resin, the structure derived from vinyl acetate monomer is preferably 1% or more and 30% or less of 100% by mass of solids, and the structure derived from vinyl chloride monomer is preferably 70% or more and 95% or less of 100% by mass.

[0105] Furthermore, from the perspective of solubility in organic solvents, substances containing hydroxyl groups derived from the vinyl alcohol structure are preferred. The hydroxyl value is preferably 20 mg KOH / g or more and 200 mg KOH / g or less. Additionally, the glass transition temperature is preferably 50°C or more and 90°C or less.

[0106] The amount of the vinyl chloride resin added is preferably 0.15% by mass or more and 80% by mass or less, more preferably 1.0% by mass or more and 50% by mass or less, relative to the total amount of ink solids.

[0107] There are no particular limitations on the colorant (B) mentioned above, and it can be appropriately selected according to the purpose. For example, common inks, coatings, and recording agents can be mentioned, as can organic pigments and inorganic pigments. They can be used alone or in combination.

[0108] Examples of organic pigments mentioned above include soluble azo, insoluble azo, azo, phthalocyanine, halogenated phthalocyanine, anthraquinone, anthraquinone, dianthraquinone, anthraquinone pyrimidine, perylene, violet ketone, quinacridone, indigo, dioxazine, isoindolineone, quinolineone, azomethylazo, flavanone, diketopyrrolopyrrole, isoindoline, indigo anthraquinone, and carbon black pigments.

[0109] Specifically, examples include Carmine 6B, Lake Red C, Permanent Red 2B, Diazo Yellow, Pyrazolone Orange, Carmine FB, Gormley Yellow, Gormley Red, Phthalocyanine Blue, Phthalocyanine Green, Dioxazine Violet, Quinacridone Fuchsin, Quinacridone Red, Indigo Anthraquinone Blue, Pyrimidine Yellow, Thionide Margaritol, Thionide Indigo Fuchsin, Perylene Red, Violet Ringerone Orange, Isoindolinone Yellow, Aniline Black, Diketopyrrolopyrrole Red, and daylight fluorescent pigments. Additionally, both untreated and acid-treated pigments can be used.

[0110] There are no particular limitations on the inorganic pigments mentioned above. From the perspective of easy observation of the ink image, gold pigments, silver pigments, or white pigments are preferred. From the perspective of making the ink image clear even with a small amount of pigment, gold pigments or silver pigments are particularly preferred.

[0111] There are no particular limitations on the aforementioned gold pigment, but flake-shaped copper powder or flake-shaped copper alloy powder (an alloy of copper and zinc, commonly known as bronze powder or gold powder) is preferred. The average particle size is preferably 1–15 μm, more preferably 3–10 μm.

[0112] There are no particular limitations on the silver pigment used, but flake aluminum or flake tin are preferred.

[0113] Examples of white pigments mentioned above include titanium dioxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silicon dioxide, zinc barium white, antimony white, and gypsum.

[0114] The aforementioned pigments are preferably included in the ink at a ratio of 5% to 90% by mass of solid content, and more preferably at a ratio of 20% to 80% by mass. Furthermore, these pigments can be used alone or in combination.

[0115] In addition, a curing agent can be used in the adhesive resin (A).

[0116] As the curing agent mentioned above, any curing agent commonly used in organic solvent-based gravure inks can be used, with isocyanate-based curing agents being the most widely used.

[0117] From the perspective of curing efficiency, the amount of isocyanate compound added is preferably 0.3% by mass or more and 10.0% by mass or less, or 1.0% by mass or more and 7.0% by mass or less, relative to the total amount of ink solids.

[0118] Relative to the total amount of solid components in the ink, the amount of binder resin (A) is preferably 0.1% by mass or more and 90% by mass or less, more preferably 0.1% by mass or more and 80% by mass or less, further preferably 1.0% by mass or more and 50% by mass or less, and most preferably 1.0% by mass or more and 40% by mass or less.

[0119] Organic solvents are preferred for use in the above inks.

[0120] There are no particular limitations on the organic solvents mentioned above. Examples include aromatic hydrocarbon organic solvents such as toluene, xylene, Solvesso #100, and Solvesso #150; aliphatic hydrocarbon organic solvents such as hexane, methylcyclohexane, heptane, octane, and silane; and various ester organic solvents such as methyl acetate, ethyl acetate, isopropyl acetate, n-propyl acetate, butyl acetate, amyl acetate, ethyl formate, and butyl propionate. In addition, examples of water-mixable organic solvents include alcohols such as methanol, ethanol, propanol, butanol, and isopropanol; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; and various glycol ethers such as ethylene glycol mono- and dimethyl ether, ethylene glycol mono- and diethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, monobutyl ether, diethylene glycol mono- and dimethyl ether, diethylene glycol mono- and diethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, triethylene glycol mono- and dimethyl ether, propylene glycol mono- and dimethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol mono- and dimethyl ether. These can be used individually or in combination.

[0121] The inks described above preferably contain an antioxidant in an amount of 0.01% by mass or more and 5.0% by mass or less relative to the total solid content of the ink.

[0122] There are no particular limitations on the antioxidants mentioned above; well-known antioxidants can be used, such as phosphite antioxidants and hindered phenolic antioxidants.

[0123] The inks described above preferably use ethyl acetate, propyl acetate, isopropanol, n-propanol, etc., and do not use aromatic solvents such as toluene or ketone solvents such as methyl ethyl ketone.

[0124] If a tackifier is used in the above ink, the adhesion strength with the above substrate can be further improved.

[0125] Examples of such adhesives include rosin-based resins, polyterpene resins, fatty acid-based petroleum resins, alicyclic petroleum resins, copolymer petroleum resins, styrene resins, and hydrogenated petroleum resins. These can be used individually or in combination. Among these, rosin-based resins are preferred.

[0126] There are no particular limitations on the above-mentioned rosin-based resins as long as they have a rosin skeleton. Preferred resins include rosin-modified maleic acid resin, rosin ester, rosin phenol, and polymerized rosin.

[0127] The softening point (based on the ring and ball method) of the above-mentioned rosin-based resin is preferably above 90°C and below 200°C.

[0128] The inks described above can be manufactured by dissolving and / or dispersing the aforementioned raw materials in an organic solvent. Commonly used dispersers such as drum mills, ball mills, pebble mills, ultrafine mills, and sand mills can be used as dispersers.

[0129] Regarding the viscosity of the aforementioned ink, whether used as a gravure ink or a flexographic ink, it is preferably 10 mPa·s or higher from the perspective of preventing pigment sedimentation and ensuring proper dispersion, and preferably 1000 mPa·s or lower from the perspective of workability during ink manufacturing and printing. It should be noted that the above viscosity was measured using a Type B viscometer manufactured by TOKIMEC at 25°C.

[0130] The viscosity of the aforementioned inks can be adjusted by appropriately selecting the type or amount of raw materials used, binder resin, pigments, organic solvents, etc. Alternatively, the viscosity can also be adjusted by regulating the particle size and particle size distribution of the pigments in the ink.

[0131] There are no particular restrictions on the ink images mentioned above; they can be selected appropriately according to the purpose, such as text or images.

[0132] Among these, it is preferable to include an identifier so that it can be easily identified as a specific adhesive tape.

[0133] There are no particular restrictions on the identifiers mentioned above; they can be chosen appropriately according to the purpose. Examples include words, numbers, graphics, lines, and symbols. Specific examples include signs, trademarks, product codes, product names, and pre-arranged displays. Among these, signs, trademarks, and product names are preferred, especially for anti-counterfeiting purposes, with registered trademarks being the most preferred.

[0134] There is no particular limitation on the size of the aforementioned identifier, and it can be appropriately selected according to the purpose. From the perspective of being able to easily identify it as a specific adhesive tape even when the size of the adhesive tape used is small, 5cm is preferred. 2 The following, or more preferably, is 4cm 2 The following, and more preferably 3cm 2 the following.

[0135] In view of the fact that the adhesive tape described above can be easily identified as a specific adhesive tape, it is preferable to include a plurality of the aforementioned identifiers.

[0136] There are no particular restrictions on the spacing of each identifier, and it can be appropriately selected according to the purpose. From the perspective that it can be easily identified as a specific adhesive tape even when the size of the adhesive tape used is small, it is preferred to be 5 cm or less, more preferably 4 cm or less, and even more preferably 3 cm or less.

[0137] The interval between the above identifiers is the distance between the end of one adjacent identifier and the end of another identifier located at the position closest to the above end, that is, the end located at the closest position.

[0138] There are no particular limitations on the arrangement of the ink image described above, but it is preferable to arrange it at an angle that is not parallel to the flow direction or width direction of the tape. A preferred example is... Figure 3A and Figure 3B This configuration is such that, typically, the tape is die-cut in the flow direction, so by arranging the ink image at an angle, the ink image can be clearly displayed on at least a portion of the surface of all the processed parts, regardless of their size (even if the parts are very small).

[0139] The observability of an ink image can be evaluated by the measurement method described in “(Observability of Ink Image)” in the examples described later.

[0140] Other measurement methods include measuring the L-shape of an ink image formed on the surface of a substrate. * Evaluations include assessing the magnitude of the brightness value and evaluating the visual effect when binarizing an image of a substrate with an ink image.

[0141] There are no particular limitations on the interlayer strength of the substrate, which can be appropriately selected according to the purpose. Preferably, it is 12 N / cm or more, more preferably 15 N / cm or more and 40 N / cm or less, and even more preferably 18 N / cm or more and 35 N / cm or less.

[0142] By keeping the interlayer strength within this range, even in the event of interlayer cracks in a soft substrate, the adhesive tape can be made easy to peel off.

[0143] The interlaminar strength was determined using the following method.

[0144] First, a 50 μm thick layer of strong adhesive is bonded to each side of the substrate for evaluating interlayer strength. Then, the substrate is cured at 40°C for 48 hours to produce a double-sided adhesive tape for interlayer strength testing.

[0145] Next, the adhesive side was supported by a 25μm thick polyester film. A double-sided adhesive tape sample, 2cm wide and 10cm long (in the flow direction of the polyolefin foam), was then applied to a stainless steel plate (the surface of which had been brushed with #360 water-resistant abrasive paper) under pressure using a 2kg roller, passing it back and forth once, at 23°C and 50% relative humidity. The sample was then placed at 40°C for 48 hours. After 24 hours at 23°C, the strength of the foam when torn along a 90-degree direction at a tensile speed of 300mm / min was measured at 23°C and 50% relative humidity.

[0146] There is no particular limitation on the 25% compressive strength of the above-mentioned substrate, and it can be appropriately selected according to the purpose, preferably 30 kPa or more and 170 kPa or less, more preferably 40 kPa or more and 150 kPa or less.

[0147] By achieving a compressive strength within the aforementioned 25% range, excellent adhesion to the substrate is achieved, particularly for substrates with uneven shapes or rough surfaces, providing excellent adhesion. Furthermore, because the substrate with this compressive strength possesses moderate cushioning properties, the pressure during adhesion is concentrated at the joint, easily squeezing out air present at the bonding interface. Therefore, even in the bonding of rigid bodies, excellent adhesion is achieved without creating gaps that allow water ingress.

[0148] The aforementioned 25% compressive strength was determined by the following method.

[0149] The specimens, cut into 50mm square pieces, are stacked until the thickness reaches approximately 10mm. The specimens are then clamped with a plate having an area larger than the specimens themselves. The specimens are compressed at 23°C at a speed of 10mm / min for approximately 2.5mm (25% of the original thickness), and then the compression is stopped. The strength is measured after 20 seconds.

[0150] There are no particular limitations on the tensile modulus of elasticity of the aforementioned substrate, which can be appropriately selected according to the purpose, but is preferably 200 N / cm. 2 above.

[0151] There is no particular limitation on the tensile strength per unit width of the above-mentioned substrate, which can be appropriately selected according to the purpose. It is preferably 10 N / cm or more, more preferably 12.5 N / cm or more, and even more preferably 14 N / cm or more.

[0152] There are no particular limitations on the cutting elongation of the aforementioned substrate, which can be appropriately selected according to the purpose, preferably 100% or more and 1000% or less, more preferably 300% or more and 700% or less.

[0153] By ensuring that the tensile modulus of elasticity, tensile strength, and elongation at break are within this range, it is possible to suppress the deterioration or breakage of the adhesive tape and to suppress the reduction in its adhesion. Furthermore, when peeling off the adhesive tape, interlayer damage to the substrate is less likely to occur, and even in the event of interlayer cracks, the adhesive tape remains easy to peel.

[0154] The tensile modulus of elasticity and the tensile strength per unit width mentioned above are the maximum strengths obtained by measuring a sample with a marking length of 2cm (flow direction of the foam substrate) and a width of 1cm using a Tensilon tensile testing machine at 23°C, 50% relative humidity, and a tensile speed of 300mm / min.

[0155] The interlaminar strength, compressive strength, and tensile modulus can be appropriately adjusted according to the material of the substrate and the foaming structure used.

[0156] When the aforementioned substrate is a foamed substrate, it is preferable to make the foaming structure of the foamed substrate into an independent bubble structure, which can effectively prevent water immersion from the cross-section of the foamed substrate. The shape of the bubbles forming the independent bubble structure is not particularly limited, but independent bubbles with a shape in which the average bubble diameter in the flow direction or width direction, or both directions, is longer than the average bubble diameter in the thickness direction of the foam have appropriate buffering characteristics.

[0157] There is no particular limitation on the foaming ratio of the above-mentioned foamed substrate, and it can be appropriately selected according to the purpose. For the reason that it is easy to achieve excellent adhesion and easy peeling with the adhered object by adjusting the above-mentioned interlayer strength, the above-mentioned compressive strength, etc. to the above-mentioned range, it is preferred to be 2 times or more and 12 times or less, more preferably 2 times or more and 8 times or less, and even more preferably 2.4 times or more and 5 times or less.

[0158] When the above-mentioned substrate is a foam substrate, the average bubble diameter in the thickness direction of the foam substrate, although depending on the thickness of the foam, is preferably 1 μm or more and 200 μm or less, more preferably 5 μm or more and 150 μm or less, and even more preferably 10 μm or more and 100 μm or less.

[0159] When the above-mentioned substrate is a foamed substrate, there is no particular limitation on the average bubble diameter in the flow direction and width direction of the foamed substrate, and it can be appropriately selected according to the purpose. Preferably, it is 1.2 μm or more and 700 μm or less, more preferably 10 μm or more and 500 μm or less, and even more preferably 100 μm or more and 400 μm or less.

[0160] By keeping the average bubble diameter within this range, it is easy to maintain independent bubbles even when the width of the adhesive tape is narrowed, and the immersion path from the cross section of the foam substrate can be properly blocked.

[0161] When the substrate is a foamed substrate, the ratio of the average bubble diameter is not particularly limited and can be appropriately selected according to the purpose. The ratio of the average bubble diameter in the flow direction of the foamed substrate to the average bubble diameter in the thickness direction (average bubble diameter in the flow direction / average bubble diameter in the thickness direction) is preferably 1.2 or more and 15 or less, more preferably 2 or more and 9 or less. Furthermore, the ratio of the average bubble diameter in the width direction of the foamed substrate to the average bubble diameter in the thickness direction (average bubble diameter in the width direction / average bubble diameter in the thickness direction) is preferably 1.2 or more and 15 or less, more preferably 2 or more and 11 or less. It is also more preferable that both the flow direction and width direction are within the above ratio range. If the ratio is 1.2 or more, it is easier to ensure flexibility in the thickness direction, thus improving conformability. Furthermore, if the ratio is 15 times or less, it is less likely to cause deviations in the flexibility and tensile strength of the foamed substrate in the flow direction and width direction.

[0162] Regarding the ratio of the average bubble diameter in the flow direction to that in the width direction, when the flow direction is set to 1, it is preferably 0.25 times or more and 4 times or less, more preferably 0.33 times or more and 3 times or less. By using the above ratio range, it is less likely to cause deviations in the softness and tensile strength of the foamed substrate in the flow direction and width direction.

[0163] The average bubble diameter in the width direction and flow direction of the above-mentioned foamed substrate was measured by the following method.

[0164] First, the foam substrate was cut into 1cm sections in both the width and flow directions. Next, the central portion of the cut foam substrate cross-section was magnified 50x using a scanning electron microscope (SEM) to photograph the cross-section in either the width or flow direction, ensuring that the entire length of the substrate's thickness was included in the photograph. In the resulting photographs, the diameter of all air bubbles present in the 2mm section of the cross-section before magnification in either the flow or width direction was measured, and the average bubble diameter was calculated based on the average value.

[0165] The average bubble diameter in the thickness direction of the above-mentioned foamed substrate was measured by the following method.

[0166] First, the thickness of the foam substrate was measured using SEM imaging. Next, SEM images were taken under the same conditions as those used to measure the average bubble diameter in the flow direction of the foam substrate. Then, in the obtained images, the number of bubbles present at any location in the thickness direction of the foam substrate was visually counted, and the average bubble diameter in the thickness direction was calculated using the following formula.

[0167] Average bubble diameter (μm) in the thickness direction = thickness of foam substrate (μm) / number of bubbles

[0168] Measure it at any three locations and take the average value as the average bubble diameter in the thickness direction.

[0169] Regarding the aforementioned substrate, in order to improve its adhesion to the aforementioned adhesive layer and other layers, surface treatments such as corona treatment, flame treatment, plasma treatment, hot air treatment, ozone / ultraviolet treatment, and coating with easy-to-adhere agents can be performed.

[0170] In the above surface treatment, by making the wetting index based on the wetting agent 36mN / m or more, preferably 40mN / m or more, and even more preferably 48mN / m or more, good adhesion to the adhesive can be obtained.

[0171] <Adhesive layer>

[0172] The adhesive layer is disposed on at least one of the substrates.

[0173] That is, the adhesive layer can be disposed on one side of the substrate or on both sides of the substrate.

[0174] The adhesive layer can be directly connected to one or both sides of the substrate, or it can be provided with other layers in between.

[0175] The adhesive layer described above comprises an adhesive composition.

[0176] The adhesive composition described above contains an adhesive and may further contain other ingredients.

[0177] -Adhesive-

[0178] There are no particular limitations on the adhesives mentioned above, and they can be selected appropriately according to the purpose. For example, known adhesives such as acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, polyester adhesives, styrene-diene block copolymer adhesives, vinyl alkyl ether adhesives, polyamide adhesives, fluorinated adhesives, creep-modified adhesives, and radiation-cured adhesives can be cited.

[0179] Among these, acrylic adhesives are preferred due to their superior bonding reliability.

[0180] Examples of acrylic adhesives include substances containing acrylic polymers.

[0181] There are no particular limitations on the acrylic polymers mentioned above, and they can be appropriately selected according to the purpose. For example, acrylic copolymers with (meth)acrylates having 4 or more and 12 or fewer carbon atoms and vinyl monomers having carboxyl groups as monomer components can be cited.

[0182] There are no particular restrictions on the (meth)acrylates with 4 or more but less than 12 carbon atoms mentioned above, and they can be appropriately selected according to the purpose. Examples include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, cyclohexyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. They can be used alone or in combination.

[0183] Among these, (meth)acrylates with 4 or more and 8 or fewer carbon atoms in the alkyl group, especially n-butyl acrylate, are preferred as they readily ensure adhesion to the substrate, exhibit excellent cohesiveness and resistance to sebum.

[0184] There is no particular limitation on the content of the aforementioned n-butyl acrylate, which can be appropriately selected according to the purpose. Preferably, it is 60% or more by mass of (meth)acrylates with a total carbon number of 4 or more and 12 or less, more preferably 90% or more by mass.

[0185] The content of the (meth)acrylate in the above-mentioned acrylic copolymer is not particularly limited and can be appropriately selected according to the purpose. Preferably, it is 80% or more and 98.5% or less by mass of the monomer components constituting the above-mentioned acrylic copolymer, more preferably 90% or more and 98.5% or less by mass.

[0186] There are no particular limitations on the vinyl monomers with carboxyl groups mentioned above, and they can be appropriately selected according to the purpose. Examples include acrylic acid, methacrylic acid, itaconic acid, maleic acid, (meth)acrylic acid dimer, crotonic acid, ethylene oxide modified succinic acid acrylate, etc.

[0187] Among these, acrylic acid is preferred as the copolymer component.

[0188] The content of the carboxyl-containing vinyl monomer in the above-mentioned acrylic copolymer is not particularly limited and can be appropriately selected according to the purpose. Preferably, it is 0.5% by mass or more and 10.0% by mass or less, more preferably 1.5% by mass or more and 5.0% by mass or less, of the monomer component constituting the acrylic copolymer.

[0189] Furthermore, when the aforementioned acrylic copolymers contain vinyl monomers with tertiary amide skeletons in the molecule as monomer components, they exhibit excellent cohesiveness and can suppress excessive increase in adhesive strength. Therefore, for materials such as polystyrene, ABS, acrylic acid, polycarbonate, polyamide polyester, polypropylene, polyurethane, phenolic resins, stainless steel, aluminum, galvanized steel sheets, and glass used as housings and components of electronic devices, they can achieve a good balance between good adhesion, reprocessing suitability, and re-peelability, making them preferred from this perspective.

[0190] There are no particular limitations on the vinyl monomers that have an intramolecular tertiary amide skeleton, and they can be appropriately selected according to the purpose. Examples include N-vinylpyrrolidone, N-vinylcaprolactam, acrylmorpholine, and N,N-dimethylacrylamide.

[0191] Among these, N-vinylpyrrolidone is preferred as the copolymer component.

[0192] The content of the vinyl monomer having an intramolecular tertiary amide backbone in the above-mentioned acrylic copolymer is not particularly limited, and can be appropriately selected according to the purpose. Preferably, it is 0.5% by mass or more and 5.0% by mass or less, more preferably 1.5% by mass or more and 3.0% by mass or less, of the monomer component constituting the above-mentioned acrylic copolymer.

[0193] When an isocyanate-based crosslinking agent is used as the crosslinking agent for the above-mentioned acrylic copolymer, a hydroxyl-containing vinyl monomer is preferably used as the vinyl monomer having a functional group that reacts with it.

[0194] There are no particular limitations on the hydroxyl-containing vinyl monomers mentioned above, and they can be appropriately selected according to the purpose. Examples include hydroxyl-containing (meth)acrylates such as (meth)acrylate-2-hydroxyethyl ester, (meth)acrylate-2-hydroxypropyl ester, (meth)acrylate-4-hydroxybutyl ester, and (meth)acrylate-6-hydroxyhexyl ester.

[0195] Among these, 2-hydroxyethyl methacrylate or 4-hydroxybutyl methacrylate are particularly preferred.

[0196] There is no particular limitation on the content of the hydroxyl-containing vinyl monomer that reacts with the isocyanate-based crosslinking agent, and it can be appropriately selected according to the purpose. Preferably, it is 0.01% by mass or more and 1.0% by mass or less, more preferably 0.03% by mass or more and 0.3% by mass or less, of the monomer component constituting the acrylic copolymer.

[0197] Other vinyl monomers include vinyl acetate, 2-acrylamide-2-methylpropanesulfonic acid and other monomers containing sulfonic acid groups, (meth)acrylates with 1 to 3 carbon atoms, (meth)acrylates with 13 or more carbon atoms, isobornyl (meth)acrylate, styrene and other known vinyl monomers.

[0198] The content of the other vinyl monomers mentioned above is not particularly limited and can be appropriately selected according to the purpose. Preferably, it is 1.5% by mass or more and 20% by mass or less in the monomer components constituting the acrylic copolymers mentioned above, more preferably 1.5% by mass or more and 10% by mass or less, and even more preferably 2% by mass or more and 8% by mass or less.

[0199] By keeping the content of the other vinyl monomers within this range, it is easy to adjust the cohesive force, holding force, and adhesiveness of the adhesive to a suitable range.

[0200] The aforementioned acrylic copolymers can be obtained by copolymerization using known polymerization methods such as solution polymerization, bulk polymerization, suspension polymerization, and emulsion polymerization. From the perspective of the adhesive's water resistance, solution polymerization and bulk polymerization are preferred. The polymerization initiation method can be arbitrarily selected, including thermal initiation methods using peroxide-based initiators such as benzoyl peroxide and lauroyl peroxide, and azo-based thermal polymerization initiators such as azobisisobutylnitrile; ultraviolet irradiation-based initiation methods using photopolymerization initiators such as acetophenone-based, benzoin ether-based, benzyl ketal-based, phosphine oxide-based, benzoin-based, and benzophenone-based initiators; electron beam irradiation-based methods; and so on.

[0201] There is no particular limitation on the molecular weight of the aforementioned acrylic copolymer, and it can be appropriately selected according to the purpose. The weight-average molecular weight converted from standard polystyrene by gel permeation chromatography (GPC) is preferably 400,000 or more and 1.6 million or less, more preferably 600,000 or more and 1.2 million or less.

[0202] -Other ingredients-

[0203] There are no particular restrictions on the other components mentioned above, and they can be selected appropriately according to the purpose. Examples include tackifying resins, colorants, crosslinking agents (curing agents), softeners, plasticizers, fillers, anti-aging agents, and residual solvents.

[0204] There are no particular limitations on the aforementioned tackifying resins, and they can be appropriately selected according to the purpose. Examples include rosin-based tackifying resins, polymerized rosin-based tackifying resins, polymerized rosin ester-based tackifying resins, rosin phenol-based tackifying resins, stabilized rosin ester-based tackifying resins, disproportionated rosin ester-based tackifying resins, hydrogenated rosin ester-based tackifying resins, terpene-based tackifying resins, terpene phenol-based tackifying resins, and petroleum resin-based tackifying resins such as styrene-based tackifying resins.

[0205] Among these, considering both adhesion to the adhered material and reprocessability and re-peelability, polymeric rosin ester-based tackifying resins are preferred.

[0206] The above-mentioned polymeric rosin ester tackifying resins can be used alone or in combination of two or more.

[0207] There is no particular limitation on the softening point of the above-mentioned polymeric rosin ester tackifying resin, and it can be appropriately selected according to the purpose. Preferably, it is 100°C or higher and 180°C or lower, more preferably 120°C or higher and 160°C or lower.

[0208] There is no particular limitation on the amount of the above-mentioned polymeric rosin ester-based tackifying resin mixed in, and it can be appropriately selected according to the purpose. It is preferably 10 parts or more and 40 parts or less, more preferably 13 parts or more and 30 parts or less, relative to 100 parts by weight of the above-mentioned acrylic copolymer.

[0209] For the purpose of adjusting the adhesion to the substrate, as well as the reprocessing suitability and re-peelability, one or more tackifying resins other than the polymeric rosin ester tackifying resins mentioned above (other tackifying resins) may be used.

[0210] Other tackifying resins mentioned above include rosin-based, polymerized rosin-based, rosin phenol-based, stabilized rosin ester-based, disproportionated rosin ester-based, hydrogenated rosin ester-based, terpene-based, terpene phenol-based, petroleum resin-based, and (meth)acrylate-based resins. When used in emulsion-type adhesive compositions, emulsion-type tackifying resins are preferred.

[0211] Among these, disproportionated rosin ester tackifying resins, rosin phenol tackifying resins, hydrogenated rosin ester tackifying resins, and (meth)acrylate resins are preferred, with disproportionated rosin ester tackifying resins having a softening point of 60°C or higher and 130°C or lower being particularly preferred.

[0212] There are no particular limitations on the mixing amount when using the other tackifying resins mentioned above, and they can be appropriately selected according to the purpose. It is preferably less than 100 parts by weight of the polymeric rosin ester tackifying resin relative to 100 parts by weight of the acrylic copolymer, and more preferably 10 parts by weight or more and 30 parts by weight or less of the total tackifying resin relative to 100 parts by weight of the acrylic copolymer. By keeping the ratio of the two within this range, it is easy to ensure a tight bond with the adhered material.

[0213] There are no particular restrictions on the colorants mentioned above; they can be selected appropriately according to the purpose, such as pigments.

[0214] There are no particular limitations on the crosslinking agents mentioned above, and they can be selected appropriately according to the purpose. For example, isocyanate-based crosslinking agents, epoxy-based crosslinking agents, metal chelate-based crosslinking agents, and azircyclopropane-based crosslinking agents can be mentioned.

[0215] Among these, crosslinking agents that are added after polymerization is terminated to carry out crosslinking reactions are preferred, and isocyanate-based or epoxy-based crosslinking agents that are highly reactive with (meth)acrylic copolymers are preferred. From the perspective of improving adhesion to the substrate, isocyanate-based crosslinking agents are more preferred.

[0216] There are no particular limitations on the above-mentioned isocyanate-based crosslinking agents, and they can be appropriately selected according to the purpose. Examples include toluene diisocyanate, naphthyl-1,5-diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, phenyl diisocyanate, and trimethylolpropane-modified toluene diisocyanate.

[0217] Among these, trifunctional polyisocyanate compounds are preferred.

[0218] There are no particular limitations on the above-mentioned trifunctional isocyanate compounds, and they can be appropriately selected according to the purpose. Examples include toluene diisocyanate and its trimethylolpropane adduct, triphenylmethane isocyanate, etc.

[0219] As an indicator of the degree of crosslinking, the gel fraction value was used, which was determined for the insoluble components after the adhesive layer was impregnated in toluene for 24 hours.

[0220] There are no particular limitations on the gel fraction mentioned above, and it can be appropriately selected according to the purpose. From the perspective of cohesiveness and adhesion, it is preferably 25% by mass or more and 70% by mass or less, more preferably 30% by mass or more and 60% by mass or less, and even more preferably 33% by mass or more and 55% by mass or less.

[0221] The gel fraction was determined by the following method.

[0222] The adhesive composition was applied to the release layer to a thickness of 65 μm after drying, dried at 100°C for 5 minutes, aged at 40°C for 2 days, and cut into 50 mm squares as samples. Next, the weight (G1) of the sample before toluene impregnation was measured. The toluene-insoluble component of the sample, after impregnation in toluene solution at 23°C for 24 hours, was separated by filtering with a 300-mesh wire mesh. After drying at 110°C for 1 hour, the weight (G2) of the residue was measured, and the gel fraction was calculated using the following formula.

[0223] Gel fraction (mass%) = (G2 / G1) × 100

[0224] There is no particular limitation on the thickness (thickness on one side) of the adhesive layer mentioned above, and it can be appropriately selected according to the purpose. From the perspective of ensuring adhesion to the adhered object even when it is a thin tape, as well as reprocessing suitability and re-peelability, it is preferred to be 10 μm or more and 100 μm or less, more preferably 30 μm or more and 80 μm or less.

[0225] <Other Layers>

[0226] There are no particular restrictions on the other layers mentioned above, and they can be appropriately selected according to the purpose. Examples include release layer, resin layer, light-shielding layer, light-reflecting layer, conductive layer, thermally conductive layer, electromagnetic wave shielding layer, etc.

[0227] There are no particular restrictions on the position of the other layers in the adhesive tape, and they can be selected appropriately according to the purpose.

[0228] -Peeling Layer-

[0229] The release layer can be disposed on the side of the adhesive layer opposite to the substrate.

[0230] The release layer can be directly connected to the adhesive layer on the side opposite to the substrate, or it can be provided with other layers in between.

[0231] There are no particular limitations on the release layer mentioned above, and it can be selected appropriately according to the purpose. For example, it can be a release layer for paper such as kraft paper, cellophane, and fiberless paper, resin films such as polyethylene, polypropylene (OPP, CPP), and polyethylene terephthalate, laminated paper formed by laminating the above-mentioned paper with resin films, and materials for which the above-mentioned paper has been treated with clay or polyvinyl alcohol for gap filling, and materials for which a silicone resin or the like has been applied to one or both sides.

[0232] There are no particular restrictions on the shape of the adhesive tape mentioned above; it can be selected appropriately according to the purpose, for example, a frame-shaped shape can be used.

[0233] There are no particular restrictions on the shape of the frame mentioned above. It can be selected appropriately according to the purpose. For example, quadrilateral, circular, star-shaped frames, or shapes with the middle hollowed out can be used.

[0234] The thickness of the adhesive tape is not particularly limited and can be appropriately selected according to the purpose, preferably 70 μm or more and 1400 μm or less. In the case of fixing components of electronic devices, especially small, thin portable electronic devices, a thin tape thickness is required, so 100 μm or more and 600 μm or less is more preferred, and 120 μm or more and 500 μm or less is even more preferred.

[0235] By making the thickness of the adhesive tape to this level, it can be used appropriately even for thin / small portable electronic devices, and good waterproofing can be achieved.

[0236] There are no particular limitations on the 180-degree peel adhesion of the aforementioned adhesive tape, and it can be appropriately selected according to the purpose. Preferably, it is 10N / 20mm or more, more preferably 25N / 20mm or more, and even more preferably 30N / 20mm or more.

[0237] The 180-degree peel adhesion was measured using the following method.

[0238] Peel off the release layer of one side of the adhesive tape, and support the exposed adhesive layer with a 25μm thick polyethylene terephthalate (PET) film. Cut the film into rectangles 300mm long and 20mm wide. Peel off the release layer of the other side, and attach the exposed adhesive layer to a stainless steel plate (SUS304 steel plate). Apply pressure with a 2kg roller in one back-and-forth motion, and then let it stand at 23°C for 1 hour to obtain a test piece. At 23°C, use a tensile testing machine (manufactured by A&D Corporation, model: RTM-100) to peel the double-sided adhesive tape from the stainless steel plate at a speed of 300mm / min in a 180-degree direction, and measure the adhesive strength.

[0239] There are no particular limitations on the holding power of the adhesive tape described above, and it can be appropriately selected according to the purpose. Preferably, it is 12 hours or more, more preferably 24 hours or more, and even more preferably 72 hours or more.

[0240] The holding power described above was measured by the following method.

[0241] Peel off the release layer of one side of the adhesive tape, support the exposed adhesive layer with a 50μm thick aluminum foil, cut it into rectangles 60mm long and 20mm wide, then peel off the release layer of the other side, and place the exposed adhesive layer according to an adhesion area of ​​400mm². 2The sample was attached to a stainless steel plate (SUS304 steel plate) in a 20mm long and 20mm wide manner. After being pressed once back and forth with a 2kg roller, it was left to stand at 23°C for 1 hour to serve as a test piece. A holding force testing machine manufactured by TESTER SANGYO Co., Ltd. was used to apply a shear load at 70°C and measure the time until it fell. It should be noted that the load condition was 500g.

[0242] There are no particular limitations on the drop impact resistance of the aforementioned adhesive tape, and it can be appropriately selected according to the purpose, preferably 50cm or more, more preferably 60cm or more, and even more preferably 70cm or more.

[0243] The aforementioned drop impact resistance was determined using the following method.

[0244] Two pieces of adhesive tape, each 20mm long and 2mm wide, are applied parallel to each other at 40mm intervals to a 2mm thick, 25mm x 50mm polycarbonate sheet. These are then applied to the center of a 2mm thick, 50mm x 50mm acrylic sheet (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Acrylite L, color: transparent). They are then subjected to a force of 50 N / cm. 2 After applying pressure for 10 seconds, the sample was left to stand at 23°C for 24 hours to serve as a test piece.

[0245] Next, a metal support was placed on the base of a DuPont impact testing machine (manufactured by TESTER SANGYO Co., Ltd.). A 300g weight was attached to the polycarbonate plate side of the test piece with adhesive tape. With the acrylic plate side of the test piece facing down, the impact core was dropped from a height of 30cm at 10-second intervals five times. After the drops, the test piece was visually inspected. If no peeling of the adhesive tape constituting the test piece or damage to the test piece was observed, the impact core was further dropped from a height of 10cm (40cm) five times at 10-second intervals.

[0246] The test was repeated to measure the drop height of the impact core when the adhesive tape constituting the test piece peeled off or the test piece was destroyed.

[0247] (Manufacturing method of adhesive tape)

[0248] The above-mentioned method for manufacturing adhesive tape includes a lamination process and may further include other processes.

[0249] <Lamination Process>

[0250] The above-mentioned lamination process is a process of laminating an adhesive layer on at least one side of a substrate.

[0251] An ink image is formed on the surface of the aforementioned substrate.

[0252] The aforementioned substrate is as described in the <Substrate> section of the (adhesive tape) above.

[0253] The adhesive layer described above is as described in the <Adhesive Layer> section of the (Adhesive Tape).

[0254] There are no particular limitations on the above-mentioned lamination method. It can be selected appropriately according to the purpose. The above-mentioned adhesive composition can be applied and laminated on the above-mentioned substrate, or it can be applied on the above-mentioned release layer and then laminated on the above-mentioned substrate.

[0255] The aforementioned release layer is as described in the "-Release Layer-" section of the <Other Layers> of the above (adhesive tape).

[0256] <Other processes>

[0257] There are no particular restrictions on other processes, and they can be selected appropriately according to the purpose. For example, ink image forming process, surface treatment process, and die-cutting process (die-cutting process) can be mentioned.

[0258] The above-described ink image forming process is a process of forming an ink image on the surface of the above-described substrate.

[0259] The ink image described above is preferably formed on the surface of the substrate in the form of a printed layer using a printing method.

[0260] There are no particular restrictions on the method for forming the above-mentioned printing layer, and it can be appropriately selected according to the purpose. For example, printing methods such as gravure printing and flexographic printing can be cited.

[0261] The above-mentioned surface treatment process is a process of treating the surface of the substrate to improve the adhesion between the substrate and the adhesive layer or other layers.

[0262] Examples of surface treatments mentioned above include corona treatment, flame treatment, plasma treatment, hot air treatment, ozone / ultraviolet treatment, and coating with an easy-to-adhere agent.

[0263] In the above surface treatment, by making the wetting index of the substrate surface based on the wetting agent 36mN / m or more, preferably 40mN / m or more, and even more preferably 48mN / m or more, good adhesion between the substrate and the adhesive layer or other layers can be obtained.

[0264] The above-mentioned die-cutting process is a process of die-cutting the adhesive tape into a frame shape or the like.

[0265] The shape of the aforementioned frame is as described in the above (adhesive tape).

[0266] There are no particular restrictions on the above-mentioned blanking methods. They can be selected appropriately according to the purpose. For example, methods such as using die-cutting blades, Thomson blades, blanking blades, dumbbell cutters, etc. can be cited.

[0267] The above-mentioned ink image forming process is performed before the above-mentioned lamination process.

[0268] The surface treatment process described above is performed before the ink image forming process or between the ink image forming process and the lamination process described above.

[0269] The above-mentioned punching process is performed after the above-mentioned lamination process or the above-mentioned surface treatment process.

[0270] That is, the adhesive tape described above can be manufactured in the following sequence.

[0271] • Ink image forming process → Surface treatment process → Lamination process → Die-cutting process

[0272] • Ink image forming process → Lamination process → Surface treatment process → Die-cutting process

[0273] Example

[0274] The following describes embodiments of the present invention, but the present invention is not limited to these embodiments in any way.

[0275] [Ink Adjustment]

[0276] -Manufacturing of acrylic resin solution Ac-

[0277] Isopropanol / ethyl acetate (in a mass ratio of 30 / 25 / 45) is added to solid acrylic resin (DIANAL BR-90 manufactured by Mitsubishi Chemical Corporation), and the mixture is stirred and dissolved to prepare a 30% solution, thus producing acrylic resin solution Ac.

[0278] -Manufacturing of polyurethane resin solution Pu-

[0279] In a 1L four-necked flask equipped with a stirrer, thermometer, Dimroth reflux cooling tube, and nitrogen inlet tube, 264.20 parts by mass of a polyester polyol with a number average molecular weight of 5100, obtained from adipic acid and 3-methyl-1,5-pentanediol, were added. Nitrogen gas was introduced, and the mixture was stirred while the temperature was raised to 50°C. Then, 28.01 parts by mass of isophorone diisocyanate were added, and the reaction was carried out at 90°C until the residual isocyanate group percentage (NCO%) reached 1.99%. After cooling, 157.34 parts by mass of n-propyl acetate were added to obtain a urethane prepolymer solution (B2) with isocyanate groups at the ends.

[0280] Next, in a 1L four-necked flask equipped with a stirrer, thermometer, Dimroth reflux cooling tube, and nitrogen inlet tube, 10.96 parts by weight of 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, 1.37 parts by weight of monoethanolamine, 411.00 parts by weight of n-propyl acetate, 142.00 parts by weight of n-propanol, and 449.55 parts by weight of urethane prepolymer solution (B2) were added. The mixture was reacted at 45°C for 4 hours to prepare a polyurethane resin solution Pu with a solid content of 30% and a weight average molecular weight of 48,000.

[0281] -Manufacturing of Polyester Resin A-

[0282] In a four-necked flask equipped with a stirrer, thermometer, reflux cooler, and nitrogen inlet tube, 50 parts by weight of isophthalic acid, 50 parts by weight of neopentyl glycol, 60 parts by weight of toluene, and 40 parts by weight of methyl ethyl ketone were added. The mixture was reacted at 80°C for 10 hours with stirring to produce polyester resin A with a resin solid content of 50% and a mass-average molecular weight of 40,000.

[0283] -Preparation of nitrocellulose resin solution N-

[0284] To 28.6 parts by weight of industrial nitrocellulose L1 / 8 (a product manufactured by Nobel Corporation with a viscosity of 1.6 to 2.9% at a solution concentration of 25.0% based on JIS K-6703), 71.4 parts by weight of a mixture of isopropanol / ethyl acetate / n-propyl acetate / methylcyclohexane (in a mass ratio of 25 / 25 / 13 / 10) were added and thoroughly mixed to prepare a nitrocellulose resin solution N with a solid content of 20%.

[0285] Preparation of cellulose acetate-propionic acid resin solution Ca-

[0286] To 20 parts by weight of cellulose acetate-propionate CAP482-0.5 (manufactured by Eastman Chemical Company), add 80 parts by weight of a mixture of isopropanol / n-propyl acetate (in a 50 / 50 ratio by weight) and mix thoroughly to prepare a cellulose acetate-propionate resin solution Ca with a solid content of 20%.

[0287] (Acrylic gold ink)

[0288] An acrylic gold ink was prepared by grinding a mixture of 20 parts by weight of the above-mentioned acrylic resin solution Ac (30% by weight of solids), 20 parts by weight of the above-mentioned nitrocellulose resin solution N (20% by weight of solids), 5 parts by weight of the above-mentioned cellulose acetate-propionate resin solution Ca (20% by weight of solids), 4 parts by weight of flaky brass metal powder (an alloy of 90% by weight of copper and 10% by weight of zinc) with an average particle size of 5 μm manufactured by mechanical grinding, 0.05 parts by weight of hindered phenolic antioxidant ADKSTAB AO-50 (manufactured by ADEKA Co., Ltd.), 15 parts by weight of isopropanol, 34.95 parts by weight of ethyl acetate, and 10 parts by weight of methylcyclohexane. The pigment concentration in the solid components of the above-mentioned acrylic gold ink was 26.6%.

[0289] (Acrylic silver ink)

[0290] An acrylic silver ink was prepared by grinding a mixture of 20 parts by weight of the above-mentioned acrylic resin solution Ac (30% by weight of solids), 20 parts by weight of the above-mentioned nitrocellulose resin solution N (20% by weight of solids), 5 parts by weight of the above-mentioned cellulose acetate-propionate resin solution Ca (20% by weight of solids), 4 parts by weight of flake tin powder with an average particle size of 10 μm manufactured by mechanical grinding, 0.05 parts by weight of hindered phenolic antioxidant ADKSTAB AO-50 (manufactured by ADEKA Co., Ltd.), 15 parts by weight of isopropanol, 34.95 parts by weight of ethyl acetate, and 10 parts by weight of methylcyclohexane. The pigment concentration in the solid components of the above-mentioned acrylic silver ink was 26.6%.

[0291] (Acrylic white ink)

[0292] An acrylic white ink was prepared by grinding a mixture of 20 parts by weight of the above-mentioned acrylic resin solution Ac (30% by weight of solids), 20 parts by weight of the above-mentioned nitrocellulose resin solution N (20% by weight of solids), 5 parts by weight of the above-mentioned cellulose acetate-propionic acid resin solution Ca (20% by weight of solids), 8 parts by weight of titanium dioxide pigment (R-780, manufactured by Ishihara Sangyo Co., Ltd.), 0.05 parts by weight of hindered phenolic antioxidant ADKSTAB AO-50 (manufactured by ADEKA Co., Ltd.), 15 parts by weight of isopropanol, 34.95 parts by weight of ethyl acetate, and 10 parts by weight of methylcyclohexane. The pigment concentration in the solid components of the above-mentioned acrylic white ink was 42.0%.

[0293] (Carbamate-based gold ink)

[0294] A mixture of 40 parts by weight of the above-mentioned polyurethane resin solution Pu (30% by weight of solids), 15 parts by weight of the above-mentioned nitrocellulose resin solution N (20% by weight of solids), 5 parts by weight of flaky brass metal powder (an alloy of 90% by weight of copper and 10% by weight of zinc) with an average particle size of 5 μm manufactured by mechanical grinding, 0.05 parts by weight of the hindered phenolic antioxidant ADKSTAB AO-50 (manufactured by ADEKA Co., Ltd.), 15 parts by weight of isopropanol, 29.95 parts by weight of ethyl acetate, and 10 parts by weight of methylcyclohexane was ground to prepare a urethane-based gold ink. The pigment concentration in the solid component of the above-mentioned urethane-based gold ink is 24.9%.

[0295] (Polyester-based gold ink)

[0296] A mixture of 12 parts by weight of the above-mentioned polyester resin A (100% by weight solids), 15 parts by weight of the above-mentioned nitrocellulose resin solution N (20% by weight solids), 5 parts by weight of flaky brass metal powder (an alloy of 90% by weight copper and 10% by weight zinc) with an average particle size of 5 μm manufactured by mechanical grinding, 0.05 parts by weight of hindered phenolic antioxidant ADKSTAB AO-50 (manufactured by ADEKA Co., Ltd.), 15 parts by weight of isopropanol, 29.95 parts by weight of ethyl acetate, and 10 parts by weight of methylcyclohexane was ground to prepare a polyester-based gold ink. The pigment concentration in the solid components of the above-mentioned polyester-based gold ink is 24.9%.

[0297] [Substrate Adjustment]

[0298] (Substrate 1)

[0299] Add 3 parts by weight of isocyanate-based curing agent (curing agent "KR90" manufactured by DIC Corporation (biuret form of hexamethylene diisocyanate, 40% by weight solid content)) to 100 parts by weight of the above-mentioned acrylic gold ink, and stir. Then, corona treatment is performed on one side of DXA030015K (polyethylene foam, 150μm thickness, 3x expansion ratio, black) manufactured by Hubei Xiangyuan New Material Technology Co., Ltd., to achieve a wetting index of 50mN / m. Gravure ink is then applied to this side, and the substrate is cured at 23°C for 5 days to prepare substrate 1. The thickness of the gravure printing layer is 4μm, and the printed pattern (ink image) is... Figure 3A and Figure 3B The registered trademarks shown are as follows. It should be noted that... Figure 3B yes Figure 3A A magnified view of a portion of the image.

[0300] (Substrate 2)

[0301] Except for changing the aforementioned acrylic gold ink to the aforementioned acrylic silver ink, substrate 2 is made in the same manner as substrate 1.

[0302] (Substrate 3)

[0303] Except for changing the aforementioned acrylic gold ink to the aforementioned acrylic white ink, substrate 3 is made in the same manner as substrate 1.

[0304] (Substrate 4)

[0305] Except for changing the acrylic gold ink to the urethane gold ink, substrate 4 is made in the same way as substrate 1.

[0306] (Base material 5)

[0307] Except for changing the aforementioned acrylic gold ink to the aforementioned polyester gold ink, substrate 5 is made in the same manner as substrate 1.

[0308] (Substrate 6)

[0309] Alternative Figure 3A and Figure 3B The registered trademark shown is used to make the printed pattern in the form of text other than the registered trademark (as “▲123” is displayed in advance), and the substrate 6 is otherwise made in the same manner as substrate 1.

[0310] (Substrate 7)

[0311] Alternative Figure 3A and Figure 3B The registered trademark shown is printed with the printed pattern as a solid print on one side of the substrate (not an ink image but printed on one side of the substrate), except that the substrate 7 is made in the same manner as substrate 1.

[0312] [Preparation of Adhesives]

[0313] Adhesive A

[0314] Solution polymerization of 97.68 parts by mass of n-butyl acrylate, 2.3 parts by mass of acrylic acid, and 0.02 parts by mass of 4-hydroxybutyl acrylate with 0.2 parts by mass of azobisisobutyronitrile (azobisisobutyronitrile) as a polymerization initiator was carried out in ethyl acetate solution at 77°C for 8 hours to obtain an acrylic polymer with a weight average molecular weight of 900,000.

[0315] In addition to 100 parts by weight of the aforementioned acrylic polymer, 5 parts by weight of "D-135" (manufactured by Arakawa Chemical Industry Co., Ltd., polymerized rosin ester), 30 parts by weight of "A100" (manufactured by Arakawa Chemical Industry Co., Ltd., disproportionated rosin ester), and 25 parts by weight of "FTR6100" (manufactured by Mitsui Chemicals Co., Ltd., petroleum resin) were mixed, and ethyl acetate was further added to obtain an adhesive solution with a solid content adjusted to 50% by weight.

[0316] The above adhesive solution was mixed and stirred with 1.1 parts by weight of "NC40" (manufactured by DIC Corporation, isocyanate crosslinking agent) to obtain adhesive A.

[0317] <Adhesive B>

[0318] 63.9 parts by mass of n-butyl acrylate, 32 parts by mass of 2-ethylhexyl acrylate, 4 parts by mass of acrylic acid, 0.1 parts by mass of 4-hydroxybutyl acrylate, and 200 parts by mass of ethyl acetate were added. The mixture was heated to 72°C while stirring and purged with nitrogen. Then, 2 parts by mass of a 2,2'-azobis(2-methylbutyronitrile) solution (0.1% by mass of solids) pre-dissolved in ethyl acetate was added to the above mixture. The mixture was kept at 72°C for 4 hours with stirring, and then at 75°C for 5 hours, thereby obtaining an acrylic polymer with a weight average molecular weight of 750,000.

[0319] 100 parts by weight of the above-mentioned acrylic polymer were mixed and stirred with 10 parts by weight of polymeric rosin ester tackifying resin D-125 (manufactured by Arakawa Chemical Industry Co., Ltd.) and 15 parts by weight of disproportionated rosin ester tackifying resin A-100 (manufactured by Arakawa Chemical Industry Co., Ltd.), and then ethyl acetate was added to obtain an adhesive solution with a solid content of 31% by weight. 100 parts by weight of this adhesive solution were mixed and stirred with 2 parts by weight of "NC40" (manufactured by DIC Corporation, an isocyanate crosslinking agent) to obtain adhesive B.

[0320] [Manufacturing of Adhesive Tape]

[0321] (Example 1)

[0322] Make the adhesive tape in the following order.

[0323] Adhesive A is applied to the release-treated surface of a 75μm thick PET film with a dry thickness of 75μm, and then dried in an oven at 85°C for 3 minutes to form an adhesive layer.

[0324] Next, both sides of the substrate 1 were corona treated to make its wetting index reach 50mN / m. The above adhesive layer was then laminated to both sides of the substrate 1 using a laminator with a linear pressure of 5kg / cm. The substrate was cured at 40°C for 2 days to produce a double-sided tape of Example 1 with a thickness of 300μm.

[0325] (Example 2)

[0326] Except that substrate 2 is used instead of substrate 1, the double-sided tape of Example 2 is made in the same manner as in Example 1.

[0327] (Example 3)

[0328] Except that substrate 3 is used instead of substrate 1, the double-sided tape of Example 3 is made in the same manner as in Example 1.

[0329] (Example 4)

[0330] Except that substrate 4 is used instead of substrate 1, the double-sided tape of Example 4 is made in the same manner as in Example 1.

[0331] (Example 5)

[0332] Except that substrate 5 is used instead of substrate 1, the double-sided tape of Example 5 is made in the same manner as in Example 1.

[0333] (Example 6)

[0334] The double-sided tape of Example 6 was made in the same manner as in Example 1, except that adhesive B was used instead of adhesive A.

[0335] (Example 7)

[0336] Except that substrate 6 is used instead of substrate 1, the double-sided tape of Example 7 is made in the same manner as in Example 1.

[0337] (Comparative Example 1)

[0338] Except for using DXA030015K (polyethylene foam, 150μm thick, 3 times expansion ratio) manufactured by Hubei Xiangyuan New Material Technology, which is not for printing layer, to replace substrate 1, the double-sided tape of Comparative Example 1 was made in the same manner as in Example 1.

[0339] (Comparative Example 2)

[0340] Add 3 parts by weight of isocyanate-based curing agent (curing agent "KR90" manufactured by DIC Corporation (biuret form of hexamethylene diisocyanate, 40% by weight solids)) to 100 parts by weight of the above-mentioned acrylic gold ink, and stir. Then, corona treat one side of the PET film to achieve a wetting index of 50 mN / m, and gravure-coat the ink onto this side, curing at 23°C for 5 days. The thickness of the gravure printing layer is 4 μm, and the printed pattern is... Figure 3A and Figure 3B The trademarks shown are registered trademarks.

[0341] The non-printed surface of the above film is subjected to release treatment to obtain a release film with printed markings (ink images). Adhesive A is applied to the release-treated surface of the release film with printed markings (ink images) to achieve a dry thickness of 75 μm, and then dried in an oven at 85°C for 3 minutes to form an adhesive layer.

[0342] Next, the two sides of DXA030015K (polyethylene foam, 150μm thick, 3 times expansion ratio) manufactured by Hubei Xiangyuan New Material Technology, which is not a printed layer, were corona treated to make its wetting index reach 50mN / m. Adhesive layers were then laminated on both sides of the substrate 1 using a laminator with a linear pressure of 5kg / cm and cured at 40°C for 2 days to produce a double-sided tape of Comparative Example 2 with a thickness of 300μm.

[0343] (Comparative Example 3)

[0344] Except that substrate 7 was used instead of substrate 1, the double-sided tape of Comparative Example 3 was made in the same manner as in Example 1.

[0345] [evaluate]

[0346] The adhesive tapes manufactured in the examples and comparative examples were evaluated using the methods described below. The results of each evaluation are shown in Table 1.

[0347] (Identifiability 1)

[0348] Visually inspect the adhesive tape before peeling off the release film and evaluate whether the product of which company can be identified according to the following criteria.

[0349] -Evaluation Criteria-

[0350] ◎: Because the registered trademark is printed on the adhesive tape, it is easily identifiable by anyone.

[0351] 〇: Since the text other than the registered trademark (the pre-arranged display) is printed on the adhesive tape, it can be identified if it is arranged in advance.

[0352] ×: Cannot be distinguished

[0353] (Identifiability 2)

[0354] Visually inspect the adhesive tape after the release film has been peeled off, and evaluate whether the product of which company can be identified according to the following criteria.

[0355] -Evaluation Criteria-

[0356] ◎: Because the registered trademark is printed on the adhesive tape, it is easily identifiable by anyone.

[0357] 〇: Since the text other than the registered trademark (the pre-arranged display) is printed on the adhesive tape, it can be identified if it is arranged in advance.

[0358] ×: Cannot be distinguished

[0359] (The ease of observation of ink images)

[0360] For the adhesive tape (31) after the release film has been peeled off, with a fluorescent lamp (32) as the light source, an observer (33) with visual acuity of 1.0 (including corrected visual acuity based on glasses or contact lenses, etc.) visually observes the ink image from a position of 35 cm away at 500 lux, with the adhesive tape (31) at an angle of 45 degrees ± 10 degrees to the ceiling (or floor) and the adhesive tape (31) at a line of sight of 90 degrees ± 10 degrees to the observer (33). The ease of observation of the ink image at this time is evaluated according to the following criteria. The fluorescent lamp is adjusted so that it is directly above the ink image. Figure 4 ).

[0361] -Evaluation Criteria-

[0362] ◎: The ink image appears clear.

[0363] 〇: The ink image appears blurry.

[0364] -: Since there is no ink image, it is not an evaluation subject.

[0365] (180-degree peel adhesion)

[0366] Peel off the release layer of one side of the adhesive tape, and support the exposed adhesive layer with a 25μm thick polyethylene terephthalate (PET) film. Cut the film into rectangles 300mm long and 20mm wide. Peel off the release layer of the other side, and attach the exposed adhesive layer to a stainless steel plate (SUS304 steel plate). After applying pressure with a 2kg roller in one back-and-forth motion, allow it to stand at 23°C for 1 hour to serve as a test piece. At 23°C, use a tensile testing machine (manufactured by A&D Corporation, model: RTM-100) to peel the double-sided adhesive tape from the stainless steel plate at a speed of 300mm / min in a 180-degree direction, and measure the adhesive strength.

[0367] (Holding force)

[0368] Peel off the release layer of one side of the adhesive tape, support the exposed adhesive layer with a 50μm thick aluminum foil, cut it into rectangles 60mm long and 20mm wide, then peel off the release layer of the other side, and place the exposed adhesive layer according to an adhesion area of ​​400mm². 2 The sample was attached to a stainless steel plate (SUS304 steel plate) in a 20mm long and 20mm wide manner. After being pressed once back and forth with a 2kg roller, it was left to stand at 23°C for 1 hour to serve as a test piece. A holding force testing machine manufactured by TESTER SANGYO Co., Ltd. was used to apply a shear load at 70°C and measure the time until it fell. It should be noted that the load condition was 500g.

[0369] The retention strength described above is evaluated according to the following criteria. Cases with an evaluation result of ◎ or ○ are considered to have excellent retention strength in practical applications.

[0370] -Evaluation Criteria-

[0371] ◎: Remained for more than 24 hours

[0372] 〇: Keep it for more than 12 hours, or drop it if it falls in less than 24 hours.

[0373] ×: Falling within 12 hours

[0374] (Indentation bond strength)

[0375] <1> At 23°C, the adhesive tape (21) obtained above is punched into a window frame shape with an outer diameter of 14mm and a width of 2mm, and then attached to an acrylic board (22) with a thickness of 2mm and an outer diameter of 20mm (Mitsubishi Rayon Corporation Acrylite (registered trademark) MR200, color: transparent, the same below) Figure 5A ).

[0376] <2> The acrylic sheet with adhesive tape prepared in (1) was attached to the SUS sheet (23) with a 9mm diameter hole, 2mm thickness, and 30×60mm in the center, with the center of the acrylic sheet (22) aligned with the center of the SUS sheet (23). After applying pressure once with a 2kg roller, the sheet was left to stand at 23°C for 1 hour to make a test piece. Figure 5B ).

[0377] <3> The peel strength of the acrylic sheet was determined by pushing the acrylic sheet through a hole in the SUS plate at a speed of 10 mm / min using a tensile testing machine equipped with a stainless steel probe (24) with an 8 mm diameter. Figure 5C ).

[0378] (Drop impact)

[0379] Two pieces of adhesive tape (11), each 20 mm long and 2 mm wide, are attached parallel to each other at 40 mm intervals on a 2 mm thick, 25 mm × 50 mm polycarbonate sheet (12). (Refer to...) Figure 6A Then, it is attached to the center of an acrylic sheet (13) (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Acrylite L, color: transparent) with a thickness of 2mm and an outer shape of 50mm×50mm (see reference). Figure 6B ). They were subjected to 50 N / cm 2 After applying pressure for 10 seconds, the sample was left to stand at 23°C for 24 hours to serve as a test piece.

[0380] Next, a metal support (15) is placed on the base of the DuPont impact testing machine (manufactured by TESTER SANGYO Co., Ltd.). A 300g weight (14) is attached to the side of the polycarbonate plate (12) of the test piece using tape (16) (see reference). Figure 6C With the acrylic plate (13) side of the test piece facing down, the impact core was dropped from a height of 30 cm five times at 10-second intervals. After the drops, the test piece was visually inspected. If no peeling of the adhesive tape (11) constituting the test piece or damage to the test piece was observed, the impact core was dropped from a position further increased by 10 cm (40 cm) five times at 10-second intervals.

[0381] The test was repeated to measure the drop height of the impact core when the adhesive tape constituting the test piece peeled off or the test piece was destroyed.

[0382] [Table 1]

[0383] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Comparative Example 1 Comparative Example 2 Comparative Example 3 Identifiability 1 ◎ ◎ ◎ ◎ ◎ ◎ ○ × ◎ × Identifiability 2 ◎ ◎ ◎ ◎ ◎ ◎ ○ × × × The ease of observation of ink images ◎ ◎ ○ ◎ ◎ ◎ ◎ - - - Adhesion strength [N 20mm] 33 33 27 25 25 26 33 31 33 32 Holding force ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ <![CDATA[Indentation strength [N / 0.96 cm 2 > 70 70 55 53 50 64 70 68 70 67 Impact resistance [cm] 70 70 60 60 60 70 70 70 70 60

[0384] As can be seen from the results in Table 1, by using an adhesive tape having a substrate and an adhesive layer on at least one of the substrate and having an ink image on the surface of the substrate, it is possible to manufacture an adhesive tape that can be easily identified as a specific adhesive tape.

[0385] Examples of embodiments of this invention include the following.

[0386] <1> An adhesive tape, characterized in that,

[0387] It has a substrate and an adhesive layer disposed on at least one of the substrates.

[0388] The surface of the aforementioned substrate has an ink image.

[0389] <2> According to the above <1> The adhesive tape wherein the light transmittance of the substrate is less than 10%.

[0390] <3> According to the above <1> The adhesive tape, wherein the substrate is black.

[0391] <4> According to the above <1> The adhesive tape wherein the ink image is gold or silver.

[0392] <5> According to the above <1> The adhesive tape wherein the ink image contains an acrylic resin.

[0393] <6> According to the above <1> The adhesive tape, wherein the ink image includes an identifier.

[0394] <7> According to the above <7> The adhesive tape, wherein the aforementioned identifier is a trademark.

[0395] <8> According to the above <1> The adhesive tape, wherein the size of the aforementioned identifier is 5cm. 2 the following.

[0396] <9> According to the above <1> The adhesive tape has multiple of the aforementioned identifiers, with each identifier spaced less than 5 cm apart.

[0397] <10> According to the above <1> The adhesive tape, wherein the substrate is a foam.

[0398] <11> According to the above <1> to <10> The adhesive tape described in any one of the above statements is in a frame-like shape.

[0399] <12> A method for manufacturing an adhesive tape, characterized in that it includes a step of laminating an adhesive layer on at least one of a substrate, wherein an ink image is formed on the surface of the substrate.

[0400] <13> According to the above <12> The method for manufacturing the adhesive tape includes a step of forming an ink image on the surface of the substrate.

[0401] <14> According to the above <13> The method for manufacturing the adhesive tape, wherein the ink image is formed on the surface of the substrate in the form of a printed layer using a printing method.

[0402] <15> According to the above <12> The method for manufacturing the adhesive tape includes a step of performing a surface treatment that gives the wettability index of the substrate surface to be 36 mN / m or higher.

[0403] <16> According to the above <12> The method for manufacturing the adhesive tape includes a step of punching the adhesive tape into a frame shape.

[0404] Explanation of reference numerals in the attached figures

[0405] 2. Substrate

[0406] 3 Adhesive layer

[0407] 4 Adhesive layer

[0408] 5. Peel-off layer

[0409] 6. Ink Images

[0410] 10 Adhesive tape

[0411] 11 Adhesive tape

[0412] 12 Polycarbonate sheets

[0413] 13 Acrylic Board

[0414] 14 weights

[0415] 15. Metal connectors

[0416] 16 Tape

[0417] 20 Adhesive tape

[0418] 21 Adhesive tape

[0419] 22 Acrylic Board

[0420] 23 SUS board

[0421] 24 Stainless Steel Probe

[0422] 31 Adhesive tape

[0423] 32 Fluorescent lamps

[0424] 33 Observers

Claims

1. An adhesive tape, characterized in that, It has a substrate and an adhesive layer disposed on at least one of the substrates. The surface of the substrate has an ink image.

2. The adhesive tape according to claim 1, wherein, The light transmittance of the substrate is less than 10%.

3. The adhesive tape according to claim 1, wherein, The substrate is black.

4. The adhesive tape according to claim 1, wherein, The ink image is gold or silver in color.

5. The adhesive tape according to claim 1, wherein, The ink image contains an identifier.

6. The adhesive tape according to claim 5, wherein, The identifier is 5cm in size. 2 the following.

7. The adhesive tape according to claim 5, wherein, The adhesive tape has a plurality of the identifiers, with each identifier spaced less than 5 cm apart.

8. The adhesive tape according to claim 1, wherein, The substrate is a foam.

9. The adhesive tape according to any one of claims 1 to 8, wherein, The adhesive tape is frame-shaped.

Images