Adhesive tape and method for manufacturing the same

Abstract

To provide an adhesive tape that can be easily identified as a specific adhesive tape, and a method for manufacturing the same. [Solution] The adhesive tape is characterized by having a base material and an adhesive layer on at least one of the base material, and having an ink image on the surface of the base material.

Description

[Technical Field]

[0001] The present invention relates to adhesive tape and a method for manufacturing the same. [Background technology]

[0002] Adhesive tape is widely used to fasten components together when making up electronic devices and other items. Patent Document 1 describes an adhesive tape that has good adhesion and conformability to the adherend, as well as excellent reworkability and re-peelability.

[0003] Adhesive tape goes through several processes before it is attached to a part. For example, when an electronics manufacturer specifies the part number and shape of the adhesive tape to be used, a die-cutting manufacturer will die-cut the specified part number of the adhesive tape into a specific shape to produce die-cut products. These die-cut products are then bonded to components by the electronics manufacturer.

[0004] Adhesive tapes have a release liner layered on top to protect the adhesive layer. This release liner often has the tape manufacturer's logo printed on it, and the presence of this logo on the release liner allows for identification of a specific adhesive tape. However, in the processing of adhesive tape, for example, the original release paper may be replaced with a different one to facilitate die-cutting. In this case, a problem arises where it becomes impossible to distinguish whether the die-cut product is made of adhesive tape other than the specific adhesive tape specified by the electronics manufacturer. As a result, problems frequently occur where the non-specific adhesive tape is incorporated into electronic devices without the manufacturer realizing it, leading to insufficient adhesive performance and peeling.

[0005] Therefore, adhesive tapes that can be easily identified as specific adhesive tapes, and methods for manufacturing the same, have not yet been provided, and there is a strong demand for their prompt provision. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2010-260880 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] The present invention aims to solve the aforementioned problems of the conventional era and achieve the following objectives. Specifically, the present invention aims to provide an adhesive tape that can be easily identified as a particular adhesive tape and a method for manufacturing the same. [Means for solving the problem]

[0008] As a result of diligent research conducted by the present inventors to achieve the above objective, they have found that it is possible to provide an adhesive tape that can be easily identified as a specific adhesive tape, and a method for manufacturing the same.

[0009] The present invention is based on the aforementioned findings by the inventors, and the means for solving the aforementioned problems are as follows: <1> The substrate comprises an adhesive layer on at least one side of the substrate, The adhesive tape is characterized by having an ink image on the surface of the substrate. <2> A method for manufacturing adhesive tape, comprising the step of laminating an adhesive layer on at least one of the substrates, characterized in that the surface of the substrate has an ink image. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide an adhesive tape that can be easily identified as a specific adhesive tape, and a method for manufacturing the same. [Brief explanation of the drawing]

[0011] [Figure 1]FIG. 1 is a schematic cross-sectional view of an adhesive tape according to one embodiment of the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view of an adhesive tape manufactured in Comparative Example 1. [Figure 3A] FIG. 3A is a diagram showing an example of an ink image. [Figure 3B] FIG. 3B is a partially enlarged view of FIG. 3A. [Figure 4] FIG. 4 is a diagram for explaining a method of evaluating the visibility of the ink image of the present invention. [Figure 5A] FIG. 5A is a diagram for explaining a method of measuring the push-in adhesion strength (a diagram of an acrylic plate with an adhesive tape attached). [Figure 5B] FIG. 5B is a diagram for explaining a method of measuring the push-in adhesion strength (a diagram of an acrylic plate with the adhesive tape in FIG. 5A attached to a SUS plate). [Figure 5C] FIG. 5C is a diagram for explaining a method of measuring the push-in adhesion strength (a diagram showing a method of measuring the push-in adhesion strength of an adhesive tape with a tensile tester). [Figure 6A] FIG. 6A is a diagram for explaining a method of measuring the drop impact resistance (a schematic view of the test piece seen from above). [Figure 6B] FIG. 6B is a diagram for explaining a method of measuring the drop impact resistance (a schematic view of the state after the test piece is attached to an acrylic plate seen from above). [Figure 6C] FIG. 6C is a diagram for explaining a method of measuring the drop impact resistance (a schematic view showing the test method of the impact resistance test). [Embodiments for Carrying Out the Invention]

[0012] (Adhesive Tape) The adhesive tape includes a base material and an adhesive layer, and may further include other layers. The adhesive layer may be provided on at least one of the base materials, and may be provided on both surfaces of the base material.

[0013] An example of the adhesive tape of the present invention is, for example, an adhesive tape (10) in which adhesive layers (3, 4) are laminated on both sides of a base material (2), as shown in Figure 1, and the adhesive tape (10) has an ink image (6) on the surface of the base material (2). The adhesive tape (10) may have a release layer (5) laminated on it.

[0014] <Base material> The substrate can support the adhesive layer.

[0015] The aforementioned substrate is not particularly limited and can be appropriately selected depending on the purpose, but a resin film is preferred. The aforementioned resin is not particularly limited and can be appropriately selected depending on the purpose, but examples include polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT), amide resins such as polyamide (nylon) and fully aromatic polyamide (aramid), polyacrylate resins such as polybutyl acrylate and polyethyl acrylate, methacrylate resins such as methyl methacrylate (PMMA), polystyrene, acrylonitrile-styrene copolymer (AS resin), and acrylonitrile-butadiene-styrene copolymer (ABS resin). Examples include styrene resins, polyether ether ketones (PEEK), polyether ketones (such as polyether ketone ketone), polyether sulfone (PES), polysulfone, polyvinyl chloride (PVC), polyphenylene sulfide (PPS), polyimide (PI), polyamide imide, polyetherimide (PEI), polyester imide, polycarbonate (PC), polyacetal, polyarylene ether (such as polyphenylene ether), polyphenylene sulfide, polyarylate, polyaryl, polyurethane resins, epoxy resins, and polyolefin resins. These resins may be used individually or in combination of two or more.

[0016] There are no particular restrictions on the aforementioned substrate, and it can be appropriately selected depending on the purpose, but a foam (foam substrate) is preferred. The foam is not particularly limited and can be appropriately selected depending on the purpose. Examples include polyolefin foams made of polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, etc., polyurethane foams, rubber foams made of acrylic rubber or other elastomers, etc. Among these, polyolefin-based foams are preferred.

[0017] There are no particular limitations on the polyolefin foam, and it can be appropriately selected depending on the purpose. For example, a crosslinked polyolefin resin foam can be obtained by supplying a polyolefin resin and a thermal decomposition type foaming agent to an extruder, melting and kneading them, and extruding the foamed polyolefin resin sheet from the extruder into a sheet shape, crosslinking the sheet with an electron beam, and then foaming, stretching, and thinning it. The aforementioned polyolefin resin can be any conventionally known resin, but it is preferable that it contains 40% by mass or more of a polyethylene resin obtained using a metallocene compound containing a tetravalent transition metal. Alternatively, the foam may be manufactured by foaming the foam, slicing the foamed sheet in the thickness direction, stretching it with a hot roll, and then applying a skin.

[0018] As additives, the aforementioned base material may optionally contain known substances such as plasticizers, softeners, antioxidants, flame retardants, fillers such as glass or plastic fibers, balloons, beads, and metal powders, colorants such as pigments and dyes, leveling agents, thickeners, water repellents, and defoamers.

[0019] There are no particular restrictions on the average thickness of the substrate, and it can be appropriately selected depending on the purpose, but it is preferably 50 μm to 1200 μm, more preferably 50 μm to 500 μm, and even more preferably 70 μm to 400 μm.

[0020] The aforementioned substrate can be a commercially available product. Examples of commercially available substrates include the polyethylene foam Volara XL-H series manufactured by Sekisui Chemical Co., Ltd., and the polyolefin series manufactured by Hubei Xiangyuan New Materials Technology Co., Ltd.

[0021] There are no particular restrictions on the light transmittance of the substrate, and it can be appropriately selected depending on the purpose. However, in order 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.

[0022] There are no particular restrictions on the color of the substrate, and it can be appropriately selected depending on the purpose, but black is preferred because it makes it easy to identify that it is a specific adhesive tape.

[0023] The substrate has an ink image on its surface. The aforementioned ink image may include colorants, resins, and the like.

[0024] There are no particular restrictions on the surface of the substrate, and it can be appropriately selected depending on the purpose. If 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 may be considered. If the adhesive layer is provided on both surfaces of the substrate, for example, the surface of the substrate on which one of the adhesive layers is provided may be considered.

[0025] The ink image is preferably formed as a printed layer on the surface of the substrate using a printing method such as gravure printing or flexographic printing.

[0026] There are no particular restrictions on the color of the ink image (the color of the coloring agent such as pigment contained in the ink image), and it can be appropriately selected depending on the purpose, but gold or silver is preferred in that it can be easily identified as a specific adhesive tape.

[0027] There are no particular restrictions on the resin contained in the aforementioned ink image, and it can be appropriately selected depending on the purpose. Examples include acrylic resins, urethane resins, and polyester resins. Among these, acrylic resin is preferred in terms of resistance to drop impact.

[0028] Any known ink can be used to form the ink image. The ink may include at least a binder resin (A) and a colorant (B).

[0029] There are no particular restrictions on the binder resin (A), and it can be appropriately selected depending on the purpose. Examples include acrylic resins, urethane resins, polyester resins, polyamide resins, cellulose resins (fiber resins), and vinyl chloride resins. These may be used individually or in combination of two or more. Among these, it is preferable that the main component of the binder resin (A) is an acrylic resin, as this does not easily reduce the adhesiveness and drop impact resistance of the tape.

[0030] The acrylic resin is not particularly limited as long as it is a copolymer of polymerizable monomers mainly composed of (meth)acrylic acid ester. Examples of polymerizable monomers include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, iso-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, iso-octyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, iso-nonyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, and phenoxyethyl (meth)acrylate. The polymerization method is not particularly limited, and monomers obtained by known bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, etc., can be used.

[0031] The weight-average molecular weight of the acrylic resin is preferably 5,000 to 200,000, and more preferably 10,000 to 100,000.

[0032] The amount of acrylic resin added is preferably 0.1% by mass or more and 80% by mass or less, relative to the total amount of ink solids, and more preferably 1.0% by mass or more and 50% by mass or less.

[0033] The polyester resin is not particularly limited as long as it is a polyester resin obtained by reacting an alcohol and a carboxylic acid using a known esterification polymerization reaction. 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-butylenediol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaerythritol, 1,4-cyclohexanediol, 1,2-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanedimethanol, spiroglycol, isosorbide, and the like. These may be used individually or in combination of two or more. Among these, polyfunctional alcohols are preferred. Examples of the aforementioned carboxylic acids include formic acid, acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, oleic acid, linoleic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, and 1,4-cyclohexanedicarboxylic acid. These may be used individually or in combination of two or more. Among these, polyfunctional carboxylic acids are preferred.

[0034] The weight-average molecular weight of the polyester resin is preferably 500 to 6000, and more preferably 1400 to 5500.

[0035] The amount of polyester resin added is preferably 0.1% by mass or more and 80% by mass or less, relative to the total amount of ink solids, and more preferably 1.0% by mass or more and 50% by mass or less.

[0036] The urethane resin is not particularly limited as long as it is a polyurethane resin obtained by reacting a polyol with a polyisocyanate. As the polyol, for example, various known polyols commonly used in the production 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, pentanediol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butylenediol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, 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 polyol may be used alone or in combination of two or more types.

[0037] In addition to the above, the polyols include polyester polyols obtained by dehydration condensation or polymerization of the low molecular weight polyols with polycarboxylic acids such as sebaic acid, adipic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, superiic acid, azelaic acid, trimellitic acid, pyromellitic acid, or their anhydrides; polyester polyols obtained by ring-opening polymerization of cyclic ester compounds, such as polycaprolactone, polyvalerolactone, poly(β-methyl-γ-valerolactone), and other lactones; and the above Examples include polycarbonate polyols obtained by reacting low molecular weight polyols with, for example, dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene; polybutadiene glycols; glycols obtained by adding ethylene oxide or propylene oxide to bisphenol A; and acrylic polyols obtained by copolymerizing, for example, acrylic acid, methacrylic acid, or their esters with one or more hydroxyethyl acrylates, hydroxypropyl acrylate, hydroxybutyl acrylate, or their corresponding methacrylic acid derivatives per molecule.

[0038] Examples of the aforementioned polyisocyanates include various known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates that are commonly used in the production of polyurethane resins. For example, 1,3-phenylenediisocyanate, 1,4-phenylenediisocyanate, 1-methyl-2,4-phenylenediisocyanate, 1-methyl-2,6-phenylenediisocyanate, 1-methyl-2,5-phenylenediisocyanate, 1-methyl-2,6-phenylenediisocyanate, 1-methyl-3,5-phenylenediisocyanate, 1-ethyl-2,4-phenylenediisocyanate, 1-isopropyl-2,4-phenylenediisocyanate, 1,3-dimethyl-2,4-phenylenediisocyanate, 1,3-dimethyl-4,6-phenylenediisocyanate, 1,4-dimethyl-2,5-phenylenediisocyanate, diethylbenzene diisocyanate, diisopropylbenzene diisocyanate, 1-methyl-3,5-diethylbenzene Aromatic polyisocyanates such as zen diisocyanate, 3-methyl-1,5-diethylbenzene-2,4-diisocyanate, 1,3,5-triethylbenzene-2,4-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, 1-methylnaphthalene-1,5-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7-diisocyanate, 1,1-dinaphthyl-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;Aliphatic or alicyclic polyisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3-cyclopentylene diisocyanate, 1,3-cyclohexylene diisocyanate, 1,4-cyclohexylene 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, and 3,3'-dimethyl-4,4'-dicyclohexylmethane diisocyanate can be used. These polyisocyanates may be used individually or in combination of two or more.

[0039] Additionally, chain elongators can be used. Examples of the chain elongators include ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, and dicyclohexylmethane-4,4'-diamine, as well as amines having hydroxyl groups in their molecules, such as 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypyropyrethylenediamine, di-2-hydroxypyropyrethylenediamine, and di-2-hydroxypropylethylenediamine. These chain elongators may be used individually or in combination of two or more.

[0040] Furthermore, monovalent active hydrogen compounds can be used as end-capping agents to stop the reaction. Examples of such compounds include dialkylamines such as di-n-butylamine and alcohols such as ethanol and isopropyl alcohol. In addition, when it is particularly desirable to introduce carboxyl groups into the polyurethane resin, amino acids such as glycine and L-alanine can be used as reaction stoppers. These end-capping agents may be used individually or in combination of two or more.

[0041] In particular, as the urethane resin, urethane resins obtained by reacting the low molecular weight polyols or the polyether polyols with the isocyanate are preferred.

[0042] The weight-average molecular weight of the urethane resin is preferably 10,000 or more and 100,000 or less, and more preferably 15,000 or more and 80,000 or less.

[0043] The amount of urethane resin added is preferably 0.1% by mass or more and 80% by mass or less, relative to the total amount of ink solids, and more preferably 1.0% by mass or more and 50% by mass or less.

[0044] Examples of the polyamide resin include thermoplastic polyamides soluble in organic solvents that can be obtained by polycondensation of a polybasic acid and a polyhydric amine. In particular, it is preferable that the polyamide resin contains a reaction product of an acid component containing polymerized fatty acids and / or dimer acids and an aliphatic and / or aromatic polyamine, and it is more preferable that it partially contains primary and secondary monoamines.

[0045] The polybasic acids used as raw materials for the polyamide resin mentioned above are not limited to the following, but include adipic acid, sebacic acid, azelaic acid, phthalic anhydride, isophthalic acid, suberic acid, glutaric acid, fumaric acid, pimelic acid, oxalic acid, malonic acid, succinic acid, maleic acid, terephthalic acid, 1,4-cyclohexyldicarboxylic acid, trimellitic acid, dimeric acid, hydrogenated dimeric acid, and polymerized fatty acids. Among these, polyamide resins containing a structure derived from dimeric acid or polymerized fatty acids as a main component (50% by mass or more in the polyamide resin) are preferred. Here, polymerized fatty acids are obtained by cyclization reactions of unsaturated fatty acids, and include monobasic fatty acids, dimerized polymerized fatty acids (dimeric acid), and trimerized polymerized fatty acids. The fatty acids constituting dimeric acid or polymerized fatty acids can preferably be derived from natural oils such as tall oil, rice bran oil, palm oil, coconut oil, and soybean oil, and those obtained from oleic acid and linoleic acid are preferred. Monocarboxylic acids can also be used in combination with polybasic 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.

[0046] Examples of the aforementioned polyhydric amines include polyamines and primary or secondary monoamines. Examples of polyamines used in polyamide resins include aliphatic diamines such as ethylenediamine, propylenediamine, hexamethylenediamine, and methylaminopropylamine, and aliphatic polyamines such as diethylenetriamine and triethylenetetramine. Examples of alicyclic polyamines include cyclohexylenediamine and isophoronediamine. Examples of aromatic aliphatic polyamines include xylylenediamine, and examples of aromatic polyamines include phenylenediamine and diaminodiphenylmethane. Furthermore, examples of primary and secondary monoamines include n-butylamine, octylamine, diethylamine, monoethanolamine, monopropanolamine, diethanolamine, and dipropanolamine.

[0047] Among these, a polyamide resin derived from rice bran oil, using rice bran fatty acids as a reaction material, is preferred. Furthermore, when rice bran fatty acids are used as a reaction material, it is preferable to use the aliphatic diamine or alicyclic polyamine as the polyhydric amine.

[0048] The number-average molecular weight of the polyamide resin is preferably 1,000 to 30,000, and more preferably 1,000 to 20,000.

[0049] The acid value of the polyamide resin is not particularly limited, but is preferably 15 mg KOH / g or less. The amine value of the polyamide resin is not particularly limited, but is preferably 10 mg KOH / g or less. The softening point of the polyamide resin is not particularly limited, but is preferably 90°C to 150°C, and more preferably 90°C to 120°C.

[0050] The amount of polyamide resin blended is preferably 1% by mass or more and 90% by mass or less, and more preferably 15% by mass or more and 80% by mass or less, relative to the total amount of ink solids.

[0051] Examples of the aforementioned cellulose-based resins (fiber-based resins) include cellulose acetate propionate, cellulose acetate butyrate, other cellulose ester resins, nitrocellulose (also known as nitrated cotton), hydroxyalkylcellulose, and carboxyalkylcellulose. The cellulose ester resin preferably has an alkyl group, and examples of such alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, and hexyl groups, and the alkyl group may also have substituents. As the cellulose-based resin, cellulose acetate propionate, cellulose acetate butyrate, or nitrocellulose are preferred, with nitrocellulose being particularly preferred.

[0052] The weight-average molecular weight of the cellulose resin (fiber resin) is preferably 5,000 to 200,000, and more preferably 10,000 to 50,000. The glass transition temperature of the cellulose resin (fiber resin) is preferably 120°C to 180°C.

[0053] The nitrocellulose (nitrified cotton) is preferably obtained as a nitrate ester by reacting natural cellulose with nitric acid, in which three hydroxyl groups in the six-membered ring of the anhydrous glucopyranose group in the natural cellulose are replaced with nitrate groups.

[0054] The nitrocellulose (nitrified cotton) is preferably one with a nitrogen content of 10% to 13% by mass and an average degree of polymerization of 30 to 500, and more preferably one with a nitrogen content of 10% to 13% by mass and an average degree of polymerization of 45 to 290.

[0055] The amount of nitrocellulose (nitrated cotton) added is preferably 0.15% by mass or more and 40% by mass or less, relative to the total amount of ink solids, and more preferably 1.0% by mass or more and 35% by mass or less.

[0056] The vinyl chloride resin is not particularly limited as long as it is a copolymer of vinyl chloride and vinyl acetate.

[0057] The weight-average molecular weight of the vinyl chloride resin is preferably 5,000 to 100,000, and more preferably 10,000 to 70,000. In the vinyl chloride resin, the structure derived from vinyl acetate monomer is preferably 1% to 30% by mass of 100% by mass of the solid content, and the structure derived from vinyl chloride monomer is preferably 70% to 95% by mass. Furthermore, from the viewpoint of solubility in organic solvents, those containing hydroxyl groups derived from the vinyl alcohol structure are also preferred. The hydroxyl value is preferably 20 mg KOH / g or more and 200 mg KOH / g or less. The glass transition temperature is preferably 50°C or more and 90°C or less. The amount of vinyl chloride resin added is preferably 0.15% by mass or more and 80% by mass or less, relative to the total amount of ink solids, and more preferably 1.0% by mass or more and 50% by mass or less.

[0058] There are no particular restrictions on the coloring agent (B), and it can be appropriately selected depending on the purpose. Examples include organic pigments and inorganic pigments used in general inks, paints, and recording materials. These may be used individually or in combination of two or more types.

[0059] Examples of the aforementioned organic pigments include soluble azo pigments, insoluble azo pigments, azo pigments, phthalocyanine pigments, halogenated phthalocyanine pigments, anthraquinone pigments, anthancerone pigments, dianthaquinonyl pigments, anthrapyrimidine pigments, perylene pigments, perinone pigments, quinacridone pigments, thioindigo pigments, dioxazine pigments, isoindolinone pigments, quinophthalone pigments, azomethine azo pigments, flavanthrone pigments, diketopyrrolopyrrole pigments, isoindoline pigments, indanthrone pigments, and carbon black pigments. Specifically, examples include carmine 6B, lake red C, permanent red 2B, disazo yellow, pyrazolone orange, carmine FB, chromophthal yellow, chromophthal red, phthalocyanine blue, phthalocyanine green, dioxazine violet, quinacridone magenta, quinacridone red, indanthrone blue, pyrimidine yellow, thioindigobordeaux, thioindigomagenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, and daylight fluorescent pigments. In addition, both unacidified and acidified pigments can be used.

[0060] The inorganic pigment is not particularly limited, but gold pigment, silver pigment, or white pigment is preferred due to the visibility of the ink image, and gold pigment or silver pigment is particularly preferred because the ink image is clearly visible even with a small amount of pigment.

[0061] The gold pigment is not particularly limited, but flake copper powder or flake copper alloy powder (an alloy of copper and zinc, commonly called bronze powder or gold powder) is preferred. The average particle size is preferably 1 to 15 μm, and more preferably 3 to 10 μm.

[0062] The silver pigment is not particularly limited, but flake aluminum or flake tin is preferred.

[0063] Examples of the aforementioned white pigments include titanium dioxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, lithopone, antimony white, and gypsum.

[0064] The aforementioned pigments are preferably included in the ink in a proportion of 5% to 90% by mass in terms of solid content, and more preferably in a proportion of 20% to 80% by mass. These pigments may be used individually or in combination of two or more.

[0065] Additionally, a hardening agent may be used in combination with the binder resin (A). As for the curing agent, a general-purpose curing agent for organic solvent-based gravure inks can be used, but isocyanate-based curing agents are the most commonly used. From the viewpoint of curing efficiency, the amount of isocyanate compound added is preferably 0.3% by mass or more and 10.0% by mass or less, and more preferably 1.0% by mass or more and 7.0% by mass or less, relative to the total amount of ink solids. The amount of binder resin (A) used is preferably 0.1% to 90% by mass, more preferably 0.1% to 80% by mass, even more preferably 1.0% to 50% by mass, and most preferably 1.0% to 40% by mass, relative to the total amount of ink solids.

[0066] It is preferable to use an organic solvent in the aforementioned ink. There are no particular restrictions on the organic solvent, but 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 decane; and various ester-based organic solvents such as methyl acetate, ethyl acetate, isopropyl acetate, n-propyl acetate, butyl acetate, amyl acetate, ethyl formate, and butyl propionate. Furthermore, examples of water-miscible organic solvents include alcohol-based solvents such as methanol, ethanol, propanol, butanol, and isopropyl alcohol; ketone-based solvents such as acetone, methyl ethyl ketone, and cycloxanone; and glycol ether-based organic solvents such as ethylene glycol (mono, di)methyl ether, ethylene glycol (mono, di)ethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, monobutyl ether, diethylene glycol (mono, di)methyl ether, diethylene glycol (mono, di)ethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, triethylene glycol (mono, di)methyl ether, propylene glycol (mono, di)methyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol (mono, di)methyl ether. These may be used individually or in combination of two or more.

[0067] Preferably, the ink contains an antioxidant in an amount of 0.01% by mass or more and 5.0% by mass or less relative to the total amount of ink solids. The antioxidant is not particularly limited, and known antioxidants can be used, such as phosphite-based antioxidants and hindered phenol-based antioxidants.

[0068] It is more preferable to use ethyl acetate, propyl acetate, isopropanol, or n-propanol in the aforementioned ink, and to avoid using aromatic solvents such as toluene or ketone-based solvents such as methyl ethyl ketone.

[0069] If a tackifier is used in the ink, the adhesion strength to the substrate can be further improved.

[0070] Examples of the tackifiers include rosin resins, polyterpene resins, fatty acid-based petroleum resins, alicyclic petroleum resins, copolymer petroleum resins, styrene resins, and hydrogenated petroleum resins. These may be used individually or in combination of two or more. Among these, rosin resins are preferred.

[0071] The rosin-based resin is not particularly limited as long as it is a resin having a rosin skeleton, but rosin-modified maleic acid resin, rosin ester, rosin phenol, polymerized rosin, etc. are preferred. The rosin-based resin is preferably one whose softening point (measured by the ring-ball method) is between 90°C and 200°C.

[0072] The ink can be manufactured by dissolving and / or dispersing the raw materials in an organic solvent. Commonly used dispersers such as roller mills, ball mills, pebble mills, attritors, and sand mills can be used.

[0073] The viscosity of the aforementioned ink is preferably in the range of 10 mPa·s or higher from the viewpoint of preventing pigment sedimentation and ensuring appropriate dispersion, whether used as a gravure ink or a flexographic ink, and 1000 mPa·s or lower from the viewpoint of workability during ink manufacturing and printing. The above viscosity was measured at 25°C using a Tokimec Type B viscometer.

[0074] The viscosity of the ink can be adjusted by appropriately selecting the type and amount of raw materials used, binder resin, pigment, organic solvent, etc. Furthermore, the viscosity of the ink can also be adjusted by adjusting the particle size and particle size distribution of the pigment in the ink.

[0075] There are no particular restrictions on the ink image, and it can be appropriately selected according to the purpose, for example, characters, images, etc. Among these, it is preferable to include an identification mark, as this makes it easy to identify that it is a specific type of adhesive tape. There are no particular restrictions on the aforementioned identifying markings, and they can be appropriately selected according to the purpose. Examples include letters, numbers, figures, lines, and symbols. Specific examples include marks, trademarks, product numbers, product names, and pre-agreed markings. Among these, marks, trademarks, and product names are particularly preferred for preventing counterfeiting, and registered trademarks are the most preferred.

[0076] There are no particular restrictions on the size of the aforementioned identification mark, and it can be appropriately selected according to the purpose. However, even when the size of the adhesive tape used is small, 5 cm is recommended so that it can be easily identified as a specific adhesive tape. 2 The following is preferable: 4cm 2 The following is more preferable, 3cm 2 The following are even more preferable.

[0077] It is preferable that the adhesive tape includes multiple identification markings so that it can be easily identified as a specific adhesive tape. There are no particular restrictions on the spacing between each identification mark, and it can be appropriately selected according to the purpose. However, even when the size of the adhesive tape used is small, a spacing of 5 cm or less is preferred, 4 cm or less is more preferred, and 3 cm or less is even more preferred, in order to make it easy to identify that it is a specific adhesive tape. The interval between each of the aforementioned identification marks is the distance from one end of an adjacent identification mark to the end of the other identification mark that is closest to that end, i.e., the distance between the closest ends.

[0078] The arrangement of the ink images is not particularly limited, but it is preferable that they be arranged diagonally rather than parallel to the flow direction or width direction of the tape. Preferred examples are the arrangements shown in Figures 3A and 3B. Since tape products are usually punched in the flow direction, arranging the ink images diagonally allows the ink images to be visibly displayed on at least a portion of the surface of any product, regardless of its size (even if the product is small).

[0079] The visibility of the ink image can be evaluated by the measurement method described in "(Visibility of Ink Image)" in the embodiments described later. Other measurement methods include measuring the L of the ink image formed on the surface of the substrate. * Methods of evaluation include evaluating based on the magnitude of the value (brightness) and evaluating based on how the image of the substrate on which the ink image is formed looks when the image is binarized.

[0080] There are no particular restrictions on the interlayer strength of the substrate, and it can be appropriately selected depending on the purpose, but it is preferably 12 N / cm or more, more preferably 15 N / cm to 40 N / cm, and even more preferably 18 N / cm to 35 N / cm. By setting the interlayer strength within this range, it is possible to make the adhesive tape easier to peel off even if interlayer cracking occurs in the flexible substrate.

[0081] The interlayer strength is measured by the following method. First, a 50 μm thick layer of strong adhesive is applied to each side of the substrate whose interlayer strength is to be evaluated. Then, it is aged at 40°C for 48 hours to produce a double-sided adhesive tape for interlayer strength measurement. Next, a 2cm wide, 10cm long (in the direction of flow of the polyolefin foam) double-sided adhesive tape sample, with one adhesive side backed by a 25μm thick polyester film, is pressed onto a stainless steel plate (with its surface treated with #360 grit waterproof abrasive paper for a hairline finish) using a 2kg roller in one pass-through motion under conditions of 23°C and 50% relative humidity, and left at 40°C for 48 hours. After being left at 23°C for 24 hours, the strength of the foam is measured when it is torn at a 90-degree angle at a tensile speed of 300mm / min under conditions of 23°C and 50% relative humidity.

[0082] There are no particular restrictions on the 25% compressive strength of the aforementioned substrate, and it can be appropriately selected depending on the purpose, but it is preferably 30kPa to 170kPa, and more preferably 40kPa to 150kPa. By setting the aforementioned 25% compressive strength within this range, excellent adhesion to the adherend is achieved, and it conforms particularly well to adherends with uneven shapes or rough surfaces, providing superior adhesion. Furthermore, because the base material with this compressive strength has moderate cushioning properties, the pressure during application is concentrated at the joint, easily pushing out air present at the adhesive interface. As a result, even when joining rigid bodies, excellent adhesion is achieved without creating gaps through which water can enter.

[0083] The aforementioned 25% compressive strength is measured by the following method. The sample, cut into 50mm squares, is stacked until it reaches a thickness of approximately 10mm. The sample is then sandwiched between plates with a larger surface area and compressed at a speed of 10mm / min at 23°C by approximately 2.5mm (25% of the original thickness). The compression is stopped, and the strength is measured after 20 seconds.

[0084] There are no particular restrictions on the tensile modulus of the aforementioned substrate, and it can be appropriately selected according to the purpose, but 200 N / cm is recommended. 2 The above is preferable. There are no particular restrictions on the tensile strength per unit width of the aforementioned substrate, and it can be appropriately selected depending on the purpose, but 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. There are no particular restrictions on the elongation at break of the substrate, and it can be appropriately selected according to the purpose, but it is preferably 100% to 1000%, and more preferably 300% to 700%. By setting the tensile modulus, tensile strength, and elongation at break within the specified range, deterioration of the processability of the adhesive tape, tearing, and reduced ease of application can be suppressed. Furthermore, interlayer fracture of the substrate is less likely to occur when peeling off the adhesive tape, and even if interlayer cracking occurs, the adhesive tape can be made easier to peel off.

[0085] The aforementioned tensile modulus and tensile strength per unit width are the maximum strengths measured using a Tensilon tensile testing machine with a gauge length of 2 cm (in the flow direction of the foam substrate) and a width of 1 cm, under measurement conditions of 23°C and 50% relative humidity, and a tensile speed of 300 mm / min.

[0086] The interlaminar strength, compressive strength, and tensile modulus can be appropriately adjusted depending on the material and foam structure of the substrate used.

[0087] When the substrate is a foam substrate, it is preferable that the foam structure of the foam substrate be a closed-cell structure, as this effectively prevents water from seeping in from the cut surface of the foam substrate. The shape of the cells forming the closed-cell structure is not particularly limited, but closed cells with a shape in which the average cell diameter in the flow direction, width direction, or both is longer than the average cell diameter in the thickness direction of the foam are preferred because they have appropriate cushioning properties. There are no particular restrictions on the foaming ratio of the foam substrate, and it can be appropriately selected according to the purpose. However, a foaming ratio of 2 to 12 is preferred, more preferably 2 to 8, and even more preferably 2.4 to 5, as this makes it easier to achieve both excellent adhesion to the adherend and ease of peeling by adjusting the interlayer strength and compressive strength to the above range.

[0088] When the substrate is a foam substrate, the average bubble diameter in the thickness direction of the foam substrate depends on the thickness of the foam, but is preferably 1 μm to 200 μm, more preferably 5 μm to 150 μm, and even more preferably 10 μm to 100 μm. When the substrate is a foam substrate, there are no particular restrictions on the average bubble diameter in the flow direction and width direction of the foam substrate, and it can be appropriately selected according to the purpose, but it is preferably 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. By setting the average bubble diameter within this range, it is easier to maintain closed bubbles even when the width of the adhesive tape is narrowed, and the water infiltration path from the cross-section of the foam substrate can be effectively blocked.

[0089] When the substrate is a foam substrate, there are no particular restrictions on the ratio of the average bubble diameters, and it can be appropriately selected according to the purpose. The ratio of the average bubble diameter in the flow direction of the foam 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, and more preferably 2 or more and 9 or less. Furthermore, the ratio of the average bubble diameter in the width direction of the foam 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, and more preferably 2 or more and 11 or less. It is even more preferable that both the flow direction and the width direction are within the above ratio range. When the ratio is 1.2 or more, flexibility in the thickness direction is easily ensured, thus improving conformability. Furthermore, when it is 15 times or less, variations in the flexibility and tensile strength of the foam substrate in the flow direction and width direction are less likely to occur.

[0090] The ratio of the average bubble diameter in the flow direction to the average bubble diameter in the width direction is preferably 0.25 to 4 times, and more preferably 0.33 to 3 times, when the flow direction is set to 1. By keeping the ratio within this range, variations in the flexibility and tensile strength of the foam substrate in the flow direction and width direction are less likely to occur.

[0091] The average bubble diameter in the width direction and flow direction of the foam substrate is measured by the following method. First, the foam substrate is cut into 1 cm sections in both the width and flow directions. Next, the central portion of the cut surface of the foam substrate is magnified 50 times using a scanning electron microscope (SEM). Then, the cross-section of the foam substrate in either the width or flow direction is photographed so that the entire length of the cut surface in the thickness direction of the substrate is captured in the photograph. In the resulting photographs, the diameter of all bubbles present in the 2 mm section of the cut surface before magnification in the flow or width direction is measured, and the average bubble diameter is calculated from the average value.

[0092] The average bubble diameter in the thickness direction of the foam substrate is measured by the following method. First, measure the thickness of the foam substrate to be photographed with a scanning electron microscope (SEM). Next, take SEM photographs under the same conditions as for measuring the average bubble diameter in the flow direction of the foam substrate. Then, visually count the number of bubbles in the thickness direction at any point in the foam substrate in the obtained photographs, and calculate the average bubble diameter in the thickness direction using the following formula. Average bubble diameter in the thickness direction (μm) = Thickness of foam substrate (μm) / Number of bubbles This measurement is taken at three arbitrary locations, and the average value is taken as the average bubble diameter in the thickness direction.

[0093] The substrate may be subjected to surface treatments such as corona treatment, flame treatment, plasma treatment, hot air treatment, ozone / ultraviolet treatment, or application of an easy-adhesion treatment agent in order to improve adhesion with the adhesive layer or other layers. The aforementioned surface treatment achieves good adhesion with the adhesive by setting the wetting index with the wetting reagent to 36 mN / m or higher, preferably 40 mN / m or higher, and more preferably 48 mN / m or higher.

[0094] <Adhesive layer> The adhesive layer is provided on at least one of the substrates. That is, the adhesive layer may be provided on one side of the substrate, or on both sides of the substrate. The adhesive layer may be provided in direct contact with one or both surfaces of the substrate, or it may be provided with another layer in between.

[0095] The adhesive layer comprises an adhesive composition. The adhesive composition includes an adhesive and may further include other components.

[0096] -Adhesive- There are no particular restrictions on the adhesive, and it can be appropriately selected depending on 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, fluorine-based adhesives, creep-type improved adhesives, and radiation-curable adhesives can be used. Among these, acrylic adhesives are preferred because they offer superior adhesive reliability.

[0097] Examples of the acrylic adhesive include those containing an acrylic polymer. The acrylic polymer is not particularly limited and can be appropriately selected depending on the purpose. Examples include acrylic copolymers having (meth)acrylate with 4 to 12 carbon atoms and vinyl monomers having carboxyl groups as monomer components.

[0098] There are no particular restrictions on the (meth)acrylate having 4 to 12 carbon atoms, and it can be appropriately selected depending on the purpose. Examples include monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, cyclohexyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. These may be used individually or in combination of two or more. Among these, (meth)acrylates with an alkyl group having 4 to 8 carbon atoms, particularly n-butyl acrylate, are preferred because they easily ensure adhesion to the substrate and have excellent cohesiveness and resistance to sebum. There are no particular restrictions on the content of the n-butyl acrylate, and it can be appropriately selected depending on the purpose, but it is preferable that all (meth)acrylates with 4 to 12 carbon atoms constitute 60% by mass or more, and more preferably 90% by mass or more.

[0099] There are no particular restrictions on the content of the (meth)acrylate in the acrylic copolymer, and it can be appropriately selected depending on the purpose, but it is preferably 80% by mass or more and 98.5% by mass or less of the monomer components constituting the acrylic copolymer, and more preferably 90% by mass or more and 98.5% by mass or less.

[0100] The vinyl monomer having a carboxyl group is not particularly limited and can be appropriately selected depending on the purpose. Examples include acrylic acid, methacrylic acid, itaconic acid, maleic acid, (meth)acrylic acid dimer, crotonic acid, and ethylene oxide-modified succinic acid acrylate. Among these, acrylic acid is preferred as a copolymerizing component.

[0101] There are no particular restrictions on the content of the vinyl monomer having a carboxyl group in the acrylic copolymer, and it can be appropriately selected depending on the purpose. However, it is preferably 0.5% by mass or more and 10.0% by mass or less, and more preferably 1.5% by mass or more and 5.0% by mass or less, of the monomer components constituting the acrylic copolymer.

[0102] Furthermore, the acrylic copolymer preferably contains a vinyl monomer having a tertiary amide skeleton as a monomer component, as this provides excellent cohesive strength while suppressing excessive adhesion. This is preferable for materials such as polystyrene, ABS, acrylic, polycarbonate, polyamide polyester, polypropylene, polyurethane, phenolic resin, metals such as stainless steel, aluminum, galvanized steel sheets, and glass, which are used for electronic equipment housings and components, as it provides both good adhesion and suitability for rework and re-peelability.

[0103] The vinyl monomer having a tertiary amide skeleton in the molecule is not particularly limited and can be appropriately selected depending on the purpose. Examples include N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, and N,N-dimethylacrylamide. Among these, N-vinylpyrrolidone is preferred as a copolymerizing component.

[0104] There are no particular restrictions on the content of vinyl monomer having a tertiary amide skeleton in the acrylic copolymer, and it can be appropriately selected depending on the purpose. However, it is preferably 0.5% by mass or more and 5.0% by mass or less, and more preferably 1.5% by mass or more and 3.0% by mass or less, of the monomer components constituting the acrylic copolymer.

[0105] When an isocyanate-based crosslinking agent is used as the crosslinking agent for the acrylic copolymer, it is preferable to use a hydroxyl group-containing vinyl monomer as the vinyl monomer having a functional group that reacts with it.

[0106] The hydroxyl group-containing vinyl monomer is not particularly limited and can be appropriately selected depending on the purpose. Examples include hydroxyl group-containing (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate. Among these, 2-hydroxyethyl (meth)acrylate or 4-hydroxybutyl (meth)acrylate are particularly preferred. There are no particular restrictions on the content of the hydroxyl group-containing vinyl monomer that reacts with the isocyanate-based crosslinking agent, and it can be appropriately selected depending on the purpose. However, it is preferably 0.01% by mass or more and 1.0% by mass or less of the monomer component constituting the acrylic copolymer, and more preferably 0.03% by mass or more and 0.3% by mass or less.

[0107] Other vinyl monomers include vinyl acetate, sulfonic acid group-containing monomers such as 2-acrylamido-2-methylpropanesulfonic acid, (meth)acrylates having 1 to 3 carbon atoms, (meth)acrylates having 13 or more carbon atoms, isobornyl (meth)acrylate, styrene, and other known vinyl monomers.

[0108] There are no particular restrictions on the content of the other vinyl monomers mentioned above, and they can be appropriately selected depending on the purpose, but it is preferably 1.5% by mass or more and 20% by mass or less in the monomer components constituting the acrylic copolymer, 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. By setting the content of the aforementioned other vinyl monomers within this range, the cohesive force, holding power, and adhesiveness of the adhesive can be easily adjusted to a suitable range.

[0109] The acrylic copolymer can be obtained by copolymerization using known polymerization methods such as solution polymerization, bulk polymerization, suspension polymerization, and emulsion polymerization, but solution polymerization and bulk polymerization are preferred due to the water resistance of the adhesive. The polymerization initiation method can also be arbitrarily selected from methods such as thermal initiation using peroxide-based thermal polymerization initiators such as benzoyl peroxide and lauroyl peroxide, or azo-based thermal polymerization initiators such as azobisisobutylnitrile, or ultraviolet irradiation initiation using acetophenone-based, benzoin ether-based, benzyl ketal-based, acylphosphine oxide-based, benzoin-based, and benzophenone-based photopolymerization initiators, or electron beam irradiation.

[0110] There are no particular restrictions on the molecular weight of the acrylic copolymer, and it can be appropriately selected depending on the purpose. However, a weight-average molecular weight in terms of standard polystyrene, as measured by gel permeation chromatography (GPC), is preferably 400,000 to 1,600,000, and more preferably 600,000 to 1,200,000.

[0111] -Other ingredients- The aforementioned other components are not particularly limited and can be appropriately selected depending on the purpose. Examples include tackifying resins, colorants, crosslinking agents (solidifying agents), softeners, plasticizers, fillers, antioxidants, and residual solvents.

[0112] There are no particular restrictions on the tackifying resin, and it 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. Among these, polymerized rosin ester-based tackifying resins are preferred because they offer a balance between adhesion to the substrate, reworkability, and re-peelability. The polymerized rosin ester-based tackifying resin may be used alone or in combination of two or more types.

[0113] There are no particular restrictions on the softening point of the polymerized rosin ester tackifying resin, and it can be appropriately selected depending on the purpose, but it is preferably 100°C to 180°C, and more preferably 120°C to 160°C.

[0114] There are no particular restrictions on the amount of the polymerized rosin ester tackifying resin used, and it can be appropriately selected depending on the purpose. However, it is preferably 10 to 40 parts by mass, and more preferably 13 to 30 parts by mass, per 100 parts by mass of the acrylic copolymer.

[0115] For the purpose of adjusting adhesion to the adherend, reworkability, and re-peelability, one or more tackifying resins other than the polymerized rosin ester-based tackifying resin (other tackifying resins) may be used. Other tackifying resins 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, it is preferable to use emulsion-type tackifying resins. Among these, disproportionate rosin ester tackifying resins, rosin phenol tackifying resins, hydrogenated rosin ester tackifying resins, and (meth)acrylate resins are preferred, with disproportionate rosin ester tackifying resins having a softening point of 60°C to 130°C being particularly preferred.

[0116] There are no particular restrictions on the amount of the other tackifying resins used, and they can be appropriately selected according to the purpose. However, it is preferable that the amount of polymerized rosin ester tackifying resin is no more than or equal to 100 parts by mass of the acrylic copolymer, and it is more preferable that the total amount of tackifying resins per 100 parts by mass of the acrylic copolymer is 10 parts by mass or more and 30 parts by mass or less. By keeping the ratio of the two within this range, it becomes easier to ensure adhesion to the adherend.

[0117] There are no particular restrictions on the coloring agent, and it can be appropriately selected depending on the purpose. Examples include pigments.

[0118] There are no particular restrictions on the crosslinking agent, and it can be appropriately selected depending on the purpose. Examples include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, metal chelate-based crosslinking agents, and aziridine-based crosslinking agents. Among these, crosslinking agents that are added after polymerization is complete to promote the crosslinking reaction are preferred, and isocyanate-based crosslinking agents or epoxy-based crosslinking agents that are highly reactive with (meth)acrylic copolymers are preferred, with isocyanate-based crosslinking agents being more preferred in that they improve adhesion to the substrate.

[0119] The isocyanate-based crosslinking agent is not particularly limited and can be appropriately selected depending on the purpose. Examples include tolylene diisocyanate, naphthylene-1,5-diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, and trimethylolpropane-modified tolylene diisocyanate. Among these, trifunctional polyisocyanate compounds are preferred. The aforementioned trifunctional isocyanate compounds are not particularly limited and can be appropriately selected depending on the purpose. Examples include tolylene diisocyanate and its trimethylolpropane adducts, and triphenylmethane isocyanate.

[0120] As an indicator of the degree of crosslinking, the gel fraction value, which is measured by the amount of insoluble material after immersing the adhesive layer in toluene for 24 hours, is used. There are no particular restrictions on the gel fraction, and it can be appropriately selected depending on the purpose, but in terms of cohesiveness and adhesion, 25% by mass or more and 70% by mass or less is preferred, 30% by mass or more and 60% by mass or less is more preferred, and 33% by mass or more and 55% by mass or less is even more preferred.

[0121] The gel fraction is measured by the following method. An adhesive composition is applied to the release layer so that the thickness after drying is 65 μm, dried at 100°C for 5 minutes, and aged at 40°C for 2 days. The resulting sample is cut into 50 mm squares and used as the sample. Next, the weight of the sample before immersion in toluene (G1) is measured in advance. After immersion in toluene solution at 23°C for 24 hours, the toluene-insoluble portion of the sample is separated by filtration through a 300-mesh wire mesh, and the weight of the residue after drying at 110°C for 1 hour (G2) is measured. The gel fraction is then determined according to the following formula. Gel fraction (mass %) = (G2 / G1) × 100

[0122] There are no particular restrictions on the thickness of the adhesive layer (thickness on one side), and it can be appropriately selected according to the purpose. However, even when using a thin tape, it is preferable that the thickness be 10 μm to 100 μm, and more preferably 30 μm to 80 μm, as this makes it easier to ensure adhesion to the substrate, reworkability, and re-peelability.

[0123] <Other layers> The aforementioned other layers are not particularly limited and can be appropriately selected according to the purpose. Examples include release layers, resin layers, light-shielding layers, light-reflecting layers, conductive layers, heat-conducting layers, and electromagnetic wave shielding layers. There are no particular restrictions on the position of the other layers in the adhesive tape, and they can be appropriately selected according to the purpose.

[0124] -Exfoliation layer- The release layer can be provided on the side of the adhesive layer opposite to the substrate. The release layer may be provided in direct contact with the side of the adhesive layer opposite to the substrate, or it may be provided with another layer in between.

[0125] There are no particular restrictions on the release layer, and it can be appropriately selected depending on the purpose. Examples include papers such as kraft paper, glassine paper, and fine paper; resin films such as polyethylene, polypropylene (OPP, CPP), and polyethylene terephthalate; laminated paper made by laminating the papers and resin films; and papers that have been treated with a sealant such as clay or polyvinyl alcohol, and then treated with a release agent such as a silicone resin on one or both sides.

[0126] There are no particular restrictions on the shape of the adhesive tape, and it can be appropriately selected according to the purpose, for example, a frame-like shape. There are no particular restrictions on the shape of the frame, and it can be appropriately selected according to the purpose. Examples include square, circular, or star-shaped frames, or frames with a hollowed-out center.

[0127] There are no particular restrictions on the thickness of the adhesive tape, and it can be appropriately selected depending on the purpose, but a thickness of 70 μm to 1400 μm is preferred. For fixing components of electronic devices, especially in the case of small, thin portable electronic devices, a thin tape thickness is required, so a thickness of 100 μm to 600 μm is more preferred, and 120 μm to 500 μm is even more preferred. By setting the thickness of the adhesive tape to the aforementioned thickness, it can be suitably applied to thin and compact portable electronic devices, and good waterproofing can be achieved.

[0128] There are no particular restrictions on the 180-degree peel adhesive strength of the adhesive tape, and it can be appropriately selected depending on the purpose, but it is preferably 10N / 20mm or more, more preferably 25N / 20mm or more, and even more preferably 30N / 20mm or more.

[0129] The aforementioned 180-degree peel adhesive strength is measured by the following method. One release layer of the adhesive tape is peeled off, and the exposed adhesive layer is backed with a 25 μm thick polyethylene terephthalate (PET film). After cutting it into a rectangle 300 mm long and 20 mm wide, the other release layer is peeled off, and the exposed adhesive layer is attached to a stainless steel plate (SUS304 steel plate). After applying pressure with a 2 kg roller for one back-and-forth motion, it is left to stand for 1 hour in a 23°C environment to be used as a test specimen. In a 23°C environment, the adhesive strength is measured when the double-sided adhesive tape is peeled off the stainless steel plate at a speed of 300 mm / min in a 180-degree direction using a tensile testing machine (manufactured by A&D Co., Ltd., model: RTM-100).

[0130] There are no particular restrictions on the holding power of the adhesive tape, and it can be appropriately selected according to the purpose, but it is preferably 12 hours or more, more preferably 24 hours or more, and even more preferably 72 hours or more.

[0131] The holding force is measured by the following method. After peeling off one release layer of the adhesive tape, the exposed adhesive layer is backed with 50 μm thick aluminum foil, cut into a rectangle 60 mm long and 20 mm wide, then the other release layer is peeled off, and the exposed adhesive layer is applied to a stainless steel plate (SUS304 steel plate) with an application area of ​​400 mm². 2 The sample is attached to a surface measuring 20mm vertically and 20mm horizontally, then compressed with a 2kg roller for one pass, and left to stand for 1 hour at 23°C. This is used as the test specimen. A holding force tester manufactured by Tester Industries Co., Ltd. is used to apply a load in the shear direction at 70°C, and the time until it falls is measured. The load condition is 500g.

[0132] There are no particular limitations on the drop impact resistance of the adhesive tape, and it can be appropriately selected according to the purpose, but a length of 50 cm or more is preferred, 60 cm or more is more preferred, and 70 cm or more is even more preferred.

[0133] The aforementioned drop impact resistance is measured by the following method. Two pieces of adhesive tape, cut to 20mm in length and 2mm in width, are attached parallel to each other with a 40mm gap between them to a 2mm thick, 25mm x 50mm polycarbonate sheet. Then, these are attached to the center of a 2mm thick, 50mm x 50mm acrylic sheet (manufactured by Mitsubishi Rayon Co., Ltd., product name: Acrylite L, color: transparent). These are then subjected to a load of 50N / cm². 2 After applying pressure for 10 seconds, the specimens were left to stand at 23°C for 24 hours to be used as test pieces. Next, a metal support is placed on the base of the DuPont impact tester (manufactured by Tester Industries Co., Ltd.). A 300g weight is attached with tape to the polycarbonate plate side of the test specimen. The impact point is dropped from a height of 30cm with the acrylic plate side of the test specimen facing downwards, five times at 10-second intervals. After the drops, the test specimen is visually inspected, and if no peeling of the adhesive tape or destruction of the test specimen is observed, the impact point is dropped again from a position 10cm higher (40cm), five times at 10-second intervals. The test is repeated, and the drop height of the impact pin is measured when peeling of the adhesive tape constituting the test piece or destruction of the test piece is observed.

[0134] (Method of manufacturing adhesive tape) The method for manufacturing the adhesive tape includes a lamination step and may further include other steps.

[0135] <Lamination process> The lamination process involves laminating an adhesive layer onto at least one of the substrates. An ink image is formed on the surface of the substrate. The aforementioned base material is as described in the <Base Material> section of the (adhesive tape) above. The adhesive layer is as described above in the section on the adhesive layer of the (adhesive tape).

[0136] There are no particular limitations on the lamination method, and it can be appropriately selected according to the purpose. The adhesive composition may be applied to the substrate and then laminated, or it may be applied to the release layer and then laminated onto the substrate. The aforementioned release layer is as described in "-Release Layer-" of the <Other Layers> of the (Adhesive Tape) above.

[0137] <Other processes> Other processes are not particularly limited and can be selected as appropriate depending on the purpose. Examples include ink image formation processes, surface treatment processes, and die-cutting processes (die-cutting processes).

[0138] The ink image formation step is a step of forming an ink image on the surface of the substrate.

[0139] Preferably, the ink image is formed on the surface of the substrate as a printed layer using a printing method.

[0140] There are no particular restrictions on the method of forming the printed layer, and it can be appropriately selected according to the purpose. Examples include gravure printing, flexographic printing, and other printing methods.

[0141] The aforementioned surface treatment step is a step of treating the surface of the substrate in order to improve the adhesion between the substrate and the adhesive layer or other layers. Examples of the aforementioned surface treatments include corona treatment, flame treatment, plasma treatment, hot air treatment, ozone / ultraviolet treatment, and application of an easy-adhesion treatment agent.

[0142] The aforementioned surface treatment ensures that the wetting index of the substrate surface with a wetting reagent is 36 mN / m or higher, preferably 40 mN / m or higher, and more preferably 48 mN / m or higher, thereby achieving good adhesion between the substrate and the adhesive layer or other layers.

[0143] The punching process is a process of punching the adhesive tape into a frame-like shape or the like. The aforementioned frame-like shape is as described above in the section on (adhesive tape).

[0144] There are no particular restrictions on the punching method, and it can be appropriately selected depending on the purpose. Examples include methods using die cutters, die cutters, punching blades, dumbbell cutters, etc.

[0145] The ink image formation step is performed before the lamination step. The surface treatment step is performed before the ink image formation step or between the ink image formation step and the lamination step. The punching step is performed after the lamination step or the surface treatment step. In other words, the adhesive tape can be manufactured in the following order. • Ink image formation process → Surface treatment process → Lamination process → Punching process • Ink image formation process → Lamination process → Surface treatment process → Punching process [Examples]

[0146] The following describes embodiments of the present invention, but the present invention is not limited in any way to these embodiments.

[0147] [Ink adjustment] -Manufacturing of acrylic resin solution Ac- A solid acrylic resin (Dianal BR-90, manufactured by Mitsubishi Chemical Corporation) was mixed with isopropyl alcohol / ethyl acetate (in a mass ratio of 30 / 25 / 45), stirred, and dissolved to prepare a 30% solution, which is then used to prepare Acrylic resin solution Ac.

[0148] -Manufacturing of polyurethane resin solution (Pu)- In a 1 L quadruple flask equipped with a stirrer, thermometer, Liebig reflux condenser, and nitrogen gas 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 charged, and the mixture was heated to 50°C while stirring and nitrogen gas was introduced. Subsequently, 28.01 parts by mass of isophorone diisocyanate was added, and the mixture was reacted at 90°C until the remaining percentage of isocyanate groups, NCO%, reached 1.99%. After cooling, 157.34 parts by mass of n-propyl acetate was added to obtain a urethane prepolymer solution (B2) having isocyanate groups at the ends. Next, in a 1 L quadruple flask equipped with a stirrer, thermometer, Liebig reflux condenser, and nitrogen gas inlet tube, 10.96 parts by mass of 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, 1.37 parts by mass of monoethanolamine, 411.00 parts by mass of n-propyl acetate, 142.00 parts by mass of n-propyl alcohol, and 449.55 parts by mass of urethane prepolymer solution (B2) were added and 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.

[0149] -Manufacturing of Polyester Resin A- In a quadruple flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 50 parts by mass of isophthalic acid, 50 parts by mass of neopentyl glycol, 60 parts by mass of toluene, and 40 parts by mass of methyl ethyl ketone were added and reacted at 80°C for 10 hours under stirring to produce polyester resin A with a resin solids content of 50% and a mass-average molecular weight of 40,000.

[0150] -Production of Nitrocellulose Resin Solution N- To 28.6 parts by mass of industrial nitrate cotton L1 / 8 (nitrocellulose, 70% solids, viscosity 1.6-2.9% at a solution concentration of 25.0% according to JIS K-6703, manufactured by Nobel), 71.4 parts by mass of a mixture of isopropyl alcohol / ethyl acetate / n-propyl acetate / methylcyclohexane (in a mass ratio of 25 / 25 / 13 / 10) was added and thoroughly mixed to prepare a nitrocellulose resin solution N with a solids content of 20%.

[0151] -Production of cellulose acetate propionate resin solution Ca- To 20 parts by mass of cellulose acetate propionate CAP482-0.5 (manufactured by Eastman Chemical), 80 parts by mass of a mixture of isopropyl alcohol and n-propyl acetate (in a 50 / 50 mass ratio) were added and thoroughly mixed to prepare a cellulose acetate propionate resin solution Ca with a solid content of 20%.

[0152] (Acrylic gold ink) An acrylic gold ink was prepared by mixing 20 parts by mass of the acrylic resin solution Ac (30% solids), 20 parts by mass of the nitrocellulose resin solution N (20% solids), 5 parts by mass of the cellulose acetate propionate resin solution Ca (20% solids), 4 parts by mass of flake brass metal powder (an alloy of 90% copper and 10% zinc) with an average particle size of 5 μm produced by mechanical grinding, 0.05 parts by mass of the hindered phenol antioxidant Adeka Stab AO-50 (manufactured by Adeka Corporation), 15 parts by mass of isopropyl alcohol, 34.95 parts by mass of ethyl acetate, and 10 parts by mass of methylcyclohexane. The pigment concentration in the solids of the acrylic gold ink was 26.6%.

[0153] (Acrylic silver ink) An acrylic silver ink was prepared by mixing 20 parts by mass of the acrylic resin solution Ac (30% solids by mass), 20 parts by mass of the nitrocellulose resin solution N (20% solids by mass), 5 parts by mass of the cellulose acetate propionate resin solution Ca (20% solids by mass), 4 parts by mass of flake tin powder with an average particle size of 10 μm produced by mechanical grinding, 0.05 parts by mass of the hindered phenol antioxidant Adeka Stab AO-50 (manufactured by Adeka Corporation), 15 parts by mass of isopropyl alcohol, 34.95 parts by mass of ethyl acetate, and 10 parts by mass of methylcyclohexane. The pigment concentration in the solids of the acrylic silver ink was 26.6%.

[0154] (Acrylic white ink) A mixture of 20 parts by mass of the acrylic resin solution Ac (30% solids), 20 parts by mass of the nitrocellulose resin solution N (20% solids), 5 parts by mass of the cellulose acetate propionate resin solution Ca (20% solids), 8 parts by mass of titanium dioxide pigment (R-780, manufactured by Ishihara Sangyo Co., Ltd.), 0.05 parts by mass of the hindered phenol antioxidant Adeka Stab AO-50 (manufactured by Adeka Corporation), 15 parts by mass of isopropyl alcohol, 34.95 parts by mass of ethyl acetate, and 10 parts by mass of methylcyclohexane was kneaded to prepare an acrylic white ink. The pigment concentration in the solids of the acrylic white ink was 42.0%.

[0155] (Urethane-based gold ink) A mixture of 40 parts by mass of the polyurethane resin solution Pu (30% solids), 15 parts by mass of the nitrocellulose resin solution N (20% solids), 5 parts by mass of flake brass metal powder (an alloy of 90% copper and 10% zinc) with an average particle size of 5 μm produced by mechanical grinding, 0.05 parts by mass of the hindered phenol antioxidant Adeka Stab AO-50 (manufactured by Adeka Corporation), 15 parts by mass of isopropyl alcohol, 29.95 parts by mass of ethyl acetate, and 10 parts by mass of methylcyclohexane was kneaded to produce a urethane-based gold ink. The pigment concentration in the solids of the urethane-based gold ink was 24.9%.

[0156] (Polyester-based gold ink) A polyester gold ink was prepared by mixing 12 parts by mass of polyester resin A (100% solids), 15 parts by mass of nitrocellulose resin solution N (20% solids), 5 parts by mass of flake brass metal powder (an alloy of 90% copper and 10% zinc) with an average particle size of 5 μm produced by mechanical grinding, 0.05 parts by mass of hindered phenol antioxidant Adeka Stab AO-50 (manufactured by Adeka Corporation), 15 parts by mass of isopropyl alcohol, 29.95 parts by mass of ethyl acetate, and 10 parts by mass of methylcyclohexane. The pigment concentration in the solids of the polyester gold ink was 24.9%.

[0157] [Preparation of the base material] (Base material 1) To 100 parts by mass of the aforementioned acrylic gold ink, 3 parts by mass of an isocyanate-based curing agent (DIC Corporation's curing agent "KR90" (biuret form of hexamethylene diisocyanate, solid content 40% by mass)) was added and stirred. Subsequently, one side of Hubei Xiangyuan New Materials Technology Co., Ltd.'s DXA030015K (polyethylene foam, thickness 150 μm, foaming ratio 3, black) was corona-treated to achieve a wetting index of 50 mN / m, and the ink was gravure-coated onto that surface. The substrate 1 was then cured at 23°C for 5 days. The thickness of the gravure-printed layer was 4 μm, and the printed pattern (ink image) was the registered trademark shown in Figures 3A and 3B. Figure 3B is a partial enlargement of Figure 3A.

[0158] (Base material 2) Substrate 2 was prepared in the same manner as substrate 1, except that the acrylic gold ink was replaced with the acrylic silver ink.

[0159] (Base material 3) Substrate 3 was prepared in the same manner as substrate 1, except that the acrylic gold ink was replaced with the acrylic white ink.

[0160] (Base material 4) Except for changing the acrylic gold ink to the urethane gold ink, the base material 4 was prepared in the same manner as base material 1.

[0161] (Base material 5) Except for changing the acrylic gold ink to the polyester gold ink, the base material 5 was prepared in the same manner as base material 1.

[0162] (Base material 6) Except for replacing the registered trademark shown in Figures 3A and 3B with characters other than the registered trademark ("▲123" as a pre-arranged indication) in the printing pattern, base material 6 was prepared in the same manner as base material 1.

[0163] (Base material 7) Substrate 7 was prepared in the same manner as Substrate 1, except that the printing pattern was replaced with a solid print (printed on the entire surface of the substrate, not just an ink image) instead of the registered trademark shown in Figures 3A and 3B.

[0164] [Preparation of adhesive] <Adhesive A> An acrylic polymer with a weight-average molecular weight of 900,000 was obtained by 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 as a polymerization initiator, in an ethyl acetate solution at 77°C for 8 hours. A tack solution was obtained by mixing 100 parts by mass of the acrylic polymer with 5 parts by mass of "D-135" (manufactured by Arakawa Chemical Industries, Ltd., polymerized rosin ester), 30 parts by mass of "A100" (manufactured by Arakawa Chemical Industries, Ltd., disproportionate rosin ester), and 25 parts by mass of "FTR6100" (manufactured by Mitsui Chemicals, Inc., petroleum resin), and then adding ethyl acetate to adjust the solid content to 50% by mass. Adhesive A was obtained by mixing the aforementioned adhesive solution with 1.1 parts by mass of "NC40" (manufactured by DIC Corporation, isocyanate crosslinking agent) and stirring.

[0165] <Adhesive B> 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 charged and heated to 72°C while stirring and blowing in nitrogen. Next, 2 parts by mass (0.1% by mass of solids) of 2,2'-azobis(2-methylbutyronitrile) solution, which had been previously dissolved in ethyl acetate, was added to the mixture and kept at 72°C for 4 hours while stirring, and then kept at 75°C for 5 hours to obtain an acrylic polymer with a weight-average molecular weight of 750,000. To 100 parts by mass of the acrylic polymer, 10 parts by mass of polymerized rosin ester tackifier D-125 (manufactured by Arakawa Chemical Industries, Ltd.) and 15 parts by mass of disproportionated rosin ester tackifier A-100 (manufactured by Arakawa Chemical Industries, Ltd.) were mixed and stirred, and then ethyl acetate was added to obtain an adhesive solution with a solid content of 31% by mass. To obtain adhesive B, 100 parts by mass of this adhesive solution was mixed with 2 parts by mass of "NC40" (manufactured by DIC Corporation, isocyanate crosslinking agent) and stirred.

[0166] [Manufacturing of adhesive tape] (Example 1) The adhesive tape was made using the following procedure. Adhesive A was applied to the release-treated surface of a 75 μm thick PET film to a dry thickness of 75 μm, and this was dried in an oven at 85°C for 3 minutes to form an adhesive layer. Next, both sides of the substrate 1 were corona-treated to achieve a wetting index of 50 mN / m, and the adhesive layer was bonded to both sides of the substrate 1 using a laminator with a linear pressure of 5 kg / cm. The material was then cured at 40°C for two days to produce a double-sided tape of Example 1 with a thickness of 300 μm.

[0167] (Example 2) The double-sided tape of Example 2 was prepared in the same manner as in Example 1, except that base material 2 was used instead of base material 1.

[0168] (Example 3) The double-sided tape of Example 3 was prepared in the same manner as in Example 1, except that base material 3 was used instead of base material 1.

[0169] (Example 4) The double-sided tape of Example 4 was prepared in the same manner as in Example 1, except that base material 4 was used instead of base material 1.

[0170] (Example 5) The double-sided tape of Example 5 was prepared in the same manner as in Example 1, except that base material 5 was used instead of base material 1.

[0171] (Example 6) The double-sided tape of Example 6 was prepared in the same manner as in Example 1, except that adhesive B was used instead of adhesive A.

[0172] (Example 7) The double-sided tape of Example 7 was prepared in the same manner as in Example 1, except that base material 6 was used instead of base material 1.

[0173] (Comparative Example 1) A double-sided tape for Comparative Example 1 was prepared in the same manner as in Example 1, except that DXA030015K (polyethylene foam, 150 μm thick, 3x foaming ratio) manufactured by Hubei Xiangyuan New Materials Technology, which does not have a printed layer, was used instead of base material 1.

[0174] (Comparative Example 2) Three parts by mass of an isocyanate-based curing agent (DIC Corporation's curing agent "KR90" (biuret form of hexamethylene diisocyanate, 40% solids by mass)) was added to 100 parts by mass of the aforementioned acrylic gold ink and stirred. Then, one side of the PET film was corona-treated to achieve a wettability of 50 mN / m, and the ink was gravure-coated onto that surface and cured at 23°C for 5 days. The thickness of the gravure-printed layer was 4 μm, and the printed pattern was the registered trademark shown in Figures 3A and 3B. A release agent was applied to the non-printed side of the above film to obtain a release film with a printed logo (ink image). Adhesive A was applied to the release surface of the release film with the printed logo (ink image) to a dry thickness of 75 μm, and this was dried in an oven at 85°C for 3 minutes to form an adhesive layer. Next, both sides of Hubei Xiangyuan New Materials Technology's DXA030015K (polyethylene foam, 150 μm thick, 3x foaming ratio), which lacked a printed layer, were corona-treated to achieve a wetting index of 50 mN / m. The adhesive layer was then laminated to both sides of substrate 1 using a laminator with a linear pressure of 5 kg / cm, and cured at 40°C for 2 days to produce a double-sided tape of Comparative Example 2 with a thickness of 300 μm.

[0175] (Comparative Example 3) A double-sided tape for Comparative Example 3 was prepared in the same manner as in Example 1, except that base material 7 was used instead of base material 1.

[0176] [evaluation] 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.

[0177] (Identifiability 1) The adhesive tape was visually inspected before the release film was removed, and its manufacturer was evaluated according to the following criteria to determine whether it was possible to identify which company produced it. -Evaluation Criteria- ◎: The registered trademark is printed on the adhesive tape, making it easily identifiable to anyone. ○: Because characters other than the registered trademark (pre-agreed markings) are printed on the adhesive tape, it is identifiable to those who have made the prior agreement. ×: Unidentifiable

[0178] (Identifiability 2) The adhesive tape, after the release film was removed, was visually inspected and evaluated according to the following criteria to determine whether it could be identified as the product of a particular company. -Evaluation Criteria- ◎: The registered trademark is printed on the adhesive tape, making it easily identifiable to anyone. ○: Because characters other than the registered trademark (pre-agreed markings) are printed on the adhesive tape, it is identifiable to those who have made the prior agreement. ×: Unidentifiable

[0179] (Ease of viewing the ink image) The visibility of the ink image of the adhesive tape (31) after the release film was peeled off was evaluated according to the following criteria when observed visually by an observer (33) with visual acuity of 1.0 (including corrected visual acuity with glasses or contact lenses, etc.) from a distance of 35 cm from the ink image, using a fluorescent lamp (32) as the light source at 500 lux, with the angle such that the adhesive tape (31) and the ceiling (or floor) were at 45 degrees ± 10 degrees, and the line of sight between the adhesive tape (31) and the observer (33) was at 90 degrees ± 10 degrees. The fluorescent lamp was adjusted to be positioned directly above the ink image (Figure 4). -Evaluation Criteria- ◎: The ink image is clearly visible. ○: The ink image appears blurry. -: No ink image available, therefore not eligible for evaluation.

[0180] (180-degree peel-off adhesive strength) One side of the adhesive tape was peeled off, and the exposed adhesive layer was backed with a 25 μm thick polyethylene terephthalate (PET film). After cutting it into a rectangle 300 mm long and 20 mm wide, the other side of the adhesive tape was peeled off, and the exposed adhesive layer was attached to a stainless steel plate (SUS304 steel plate). After applying pressure with a 2 kg roller for one back-and-forth motion, it was left to stand for 1 hour at 23°C to be used as a test specimen. At 23°C, the adhesive strength was measured using a tensile testing machine (manufactured by A&D Co., Ltd., model: RTM-100) when the double-sided adhesive tape was peeled off the stainless steel plate at a speed of 300 mm / min in a 180-degree direction.

[0181] (holding force) After peeling off one side of the adhesive tape's release layer and backing the exposed adhesive layer with 50μm thick aluminum foil, cut it into a rectangle 60mm long and 20mm wide, peel off the other side of the release layer and apply the exposed adhesive layer to a stainless steel plate (SUS304 steel plate) with an application area of ​​400mm². 2 The sample was attached to a surface measuring 20mm vertically and 20mm horizontally, then compressed and pressed once back and forth with a 2kg roller. After that, it was left to stand for 1 hour in a 23°C environment, and this was used as the test specimen. Using a holding force tester manufactured by Tester Sangyo Co., Ltd., a load was applied in the shear direction in a 70°C environment, and the time until it fell was measured. The load condition was 500g.

[0182] The holding force was evaluated according to the following criteria. Those with an evaluation result of ◎ or ○ were evaluated as having excellent holding force in practical use. -Evaluation criteria- ◎: Held for 24 hours or more 〇: Held for 12 hours or more and fell before 24 hours ×: Fell before 12 hours

[0183] (Push-in adhesion strength) <1> At 23°C, on an acrylic plate (22) with a thickness of 2 mm and a size of 20 mm square (Mitsubishi Rayon Co., Ltd. Acrylite (registered trademark) MR200, hue: transparent, the same hereinafter), the adhesive tape (21) obtained above was cut into a window frame shape with an outer shape of 14 mm square and a width of 2 mm and pasted (Figure 5A).

[0184] <2> On a rectangular SUS plate (23) with a thickness of 2 mm, a size of 30×60 mm, and a 9-mm-diameter hole in the center, the acrylic plate with the adhesive tape prepared in (1) was pasted so that the centers of the acrylic plate (22) and the SUS plate (23) coincided, pressed once back and forth with a 2-kg roller, and then left standing at 23°C for 1 hour to obtain a test piece (Figure 5B).

[0185] <3> From the SUS side of the test piece, through the hole in the SUS plate, an acrylic plate was pushed at 10 mm / min with a tensile testing machine equipped with a stainless steel probe (24) with a diameter of 8 mm, and the strength at which the acrylic plate peeled off was measured (Figure 5C).

[0186] (Drop impact resistance) On a polycarbonate plate (12) with a thickness of 2 mm and an outer shape of 25 mm×50 mm, two adhesive tapes (11) cut to a length of 20 mm and a width of 2 mm were pasted in parallel with a 40-mm interval (see Figure 6A), and then pasted to the central part of an acrylic plate (13) (manufactured by Mitsubishi Rayon Co., Ltd., product name: Acrylite L, hue: transparent) with a thickness of 2 mm and an outer shape of 50 mm×50 mm (see Figure 6B). After pressing them at 50 N / cm 2 for 10 seconds, the ones left standing at 23°C for 24 hours were used as test pieces. Next, a metal support (15) was placed on the base of a DuPont impact tester (manufactured by Tester Industries Co., Ltd.). A 300g weight (14) was attached to the polycarbonate plate (12) side of the test specimen with tape (16) (see Figure 6C). The impact pin was dropped from a height of 30cm with the acrylic plate (13) side of the test specimen facing downwards, five times at 10-second intervals. After the drops, the test specimen was visually inspected, and if no peeling of the adhesive tape (11) or destruction of the test specimen was observed, the impact pin was dropped again from a position 10cm higher (40cm), five more times at 10-second intervals. The same tests were repeated, and the drop height of the impact pin was measured when peeling of the adhesive tape constituting the test piece or destruction of the test piece was observed.

[0187] [Table 1]

[0188] The results in Table 1 show that an adhesive tape can be manufactured that is easily identifiable as a specific adhesive tape by having a base material and an adhesive layer on at least one of the base materials, and having an ink image on the surface of the base material.

[0189] Examples of embodiments of the present invention include the following: <1> The substrate comprises an adhesive layer on at least one side of the substrate, The adhesive tape is characterized by having an ink image on the surface of the substrate. <2> The light transmittance of the substrate is 10% or less. <1> This is the adhesive tape described in [the document]. <3> The color of the substrate is black, <1> This is the adhesive tape described in [the document]. <4> The color of the aforementioned ink image is gold or silver, <1> This is the adhesive tape described in [the document]. <5> The ink image contains an acrylic resin, <1> This is the adhesive tape described in [the document]. <6> The ink image includes an identification mark, <1> This is the adhesive tape described in [the document]. <7> The aforementioned identification mark is a trademark, <7> This is the adhesive tape described in [the document]. <8> The size of the aforementioned identification mark is 5 cm 2 The following is the aforementioned <1> This is the adhesive tape described in [the document]. <9> The invention has multiple identification markings, and the interval between each identification marking is 5 cm or less. <1> This is the adhesive tape described in [the document]. <10> The substrate is a foam, <1> This is the adhesive tape described in [the document]. <11> The above-mentioned frame-shaped <1> from <10> It is an adhesive tape as described in one of the following. <12> The method for manufacturing an adhesive tape includes a step of laminating an adhesive layer on at least one of the substrates, characterized in that an ink image is formed on the surface of the substrate. <13> The process includes forming an ink image on the surface of the substrate, <12> A method for manufacturing adhesive tape as described above. <14> The ink image is formed on the surface of the substrate as a printed layer using a printing method. <13> A method for manufacturing adhesive tape as described above. <15> The process includes a step of performing a surface treatment to obtain a wettability index of 36 mN / m or more on the surface of the substrate, <12> A method for manufacturing adhesive tape as described above. <16> The process includes punching out the adhesive tape into a frame-like shape, <12> This is a method for manufacturing adhesive tape as described above. [Explanation of Symbols]

[0190] 2 Base material 3. Adhesive layer 4. Adhesive layer 5. Delamination layer 6 Ink Images 10 Adhesive Tapes 11 Adhesive tape 12 Polycarbonate sheet 13 Acrylic sheet 14 weights 15 Metal mounts 16 tapes 20 Adhesive Tapes 21 Adhesive tape 22 Acrylic sheet 23 SUS board 24 Stainless steel probes 31 Adhesive tape 32 fluorescent lamps 33 Observer

Claims

1. The substrate comprises an adhesive layer on at least one side of the substrate, An adhesive tape characterized by having an ink image on the surface of the substrate.

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

3. The adhesive tape according to claim 1, wherein the color of the base material is black.

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

5. The adhesive tape according to claim 1, wherein the ink image contains an acrylic resin.

6. The adhesive tape according to claim 1, wherein the ink image includes an identification mark.

7. The adhesive tape according to claim 6, wherein the aforementioned identification mark is a trademark.

8. The size of the aforementioned identification mark is 5 cm ２ The adhesive tape according to claim 1, which is as follows:

9. The adhesive tape according to claim 1, wherein it has multiple identification marks, and the interval between each identification mark is 5 cm or less.

10. The adhesive tape according to claim 1, wherein the base material is a foam.

11. An adhesive tape according to any one of claims 1 to 10, having a frame-like shape.

12. The process includes laminating an adhesive layer onto at least one of the substrates, A method for manufacturing an adhesive tape, characterized in that an ink image is formed on the surface of the substrate.

13. A method for manufacturing an adhesive tape according to claim 12, comprising the step of forming an ink image on the surface of the substrate.

14. The method for manufacturing an adhesive tape according to claim 13, wherein the ink image is formed on the surface of the substrate as a printed layer using a printing method.

15. A method for manufacturing an adhesive tape according to claim 12, comprising the step of performing a surface treatment to obtain a wettability index of 36 mN / m or more on the surface of the substrate.

16. The method for manufacturing an adhesive tape according to claim 12, further comprising the step of punching out the adhesive tape into a frame-like shape.

Images