Adhesive tape, and wire harness

Abstract

To provide an adhesive tape which is excellent in film formation property even when a base material is thinned, and has high base material strength.SOLUTION: An adhesive tape includes a base material layer composed of a resin composition containing a thermoplastic resin, and an adhesive layer provided on one surface of the base material layer. The resin composition contains 2 pts.mass or less of calcium carbonate, and more than 28 pts.mass and less than 40 pts.mass of a plasticizer, with respect to 100 pts.mass of the thermoplastic resin. The other surface of the base material layer further contains unevenness.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an adhesive tape and a wire harness. [Background technology]

[0002] As various adhesive films such as insulating tapes used in various electrical devices in automobiles, railways, aircraft, ships, houses, factories, etc., adhesive tapes in which an adhesive is applied to one side of a substrate made from a resin composition containing a thermoplastic resin are used because they have appropriate flexibility and extensibility, excellent flame retardancy, mechanical strength, heat deformation resistance, electrical insulation properties, and moldability, and are relatively inexpensive (Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-209718 [Patent Document 2] International Publication No. 2019 / 049565 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been a demand for such pressure-sensitive adhesive tapes to be lighter, i.e., for thinner substrates and pressure-sensitive adhesive layers, in order to improve fuel efficiency in automobiles and aircraft, for example. However, when the substrate layer is thinned, film-forming properties and substrate strength may be reduced.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pressure-sensitive adhesive tape that has excellent film-forming properties and high substrate strength even when the substrate layer is made thin. [Means for solving the problem]

[0006] As a result of extensive research, the present inventors have found that the above-mentioned problems can be solved by adjusting the composition of the base material, and have thus completed the present invention.

[0007] According to the present invention, the following is provided: [1] An adhesive tape comprising a substrate layer made of a resin composition containing a thermoplastic resin, and an adhesive layer provided on one surface of the substrate layer, wherein the resin composition contains 2 parts by mass or less of calcium carbonate and more than 28 parts by mass but less than 40 parts by mass of a plasticizer per 100 parts by mass of the thermoplastic resin, and the other surface of the substrate layer has irregularities. [2] The pressure-sensitive adhesive tape according to [1], wherein the difference between the maximum thickness and the minimum thickness of the base layer is within 30% of the thickness of the base layer. [3] The pressure-sensitive adhesive tape according to [1] or [2], wherein the other surface has an arithmetic mean roughness Ra of 0.10 to 2.00 μm. [4] The pressure-sensitive adhesive tape according to any one of [1] to [3], wherein the thickness of the pressure-sensitive adhesive tape is 75 μm or less. [5] The pressure-sensitive adhesive tape according to any one of [1] to [4], wherein the pressure-sensitive adhesive layer has a thickness of 15 μm or less. [6] The pressure-sensitive adhesive tape according to any one of [1] to [5], wherein the resin composition does not contain an inorganic filler. [7] The pressure-sensitive adhesive tape according to any one of [1] to [6], wherein the thermoplastic resin contains a vinyl chloride resin. [8] The pressure-sensitive adhesive tape according to any one of [1] to [7], which is used for bundling electric wires. [9] A wire harness comprising electric wires and the adhesive tape according to any one of [1] to [8] for bundling the electric wires. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a pressure-sensitive adhesive tape that has excellent film-forming properties and high substrate strength even when the substrate layer is thinned. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be described in detail below. The present invention is not limited to these descriptions. Each feature of the embodiments shown below can be combined with each other. Also, an invention can be established independently for each feature. Further, among the following embodiments, elements not defined in the claims are optional elements and thus can be omitted.

[0010] <Explanation of Terms> In this specification, for example, the description "X to Y" means X or more and Y or less. In this specification, for example, the description "within the range between any two of the exemplified numerical values" means that when the exemplified numerical values are A and B (A < B), it is A or more or more than A and B or less or less than B.

[0011] 1 Adhesive Tape The adhesive tape according to this embodiment includes a base material layer and an adhesive layer. The adhesive layer according to this embodiment is provided on one surface (single side) of the base material layer. Also, for the adhesive tape according to this embodiment, the adhesive layer may be directly provided on one surface of the base material layer, or the adhesive layer may be provided via another layer (for example, the undercoat layer described later).

[0012] The thickness of the pressure-sensitive adhesive tape according to this embodiment is preferably 100 μm or less, more preferably 80 μm or less, even more preferably 75 μm or less, and particularly preferably 70 μm or less. The lower limit of the thickness of the pressure-sensitive adhesive tape according to this embodiment is not particularly limited, but is, for example, 45 μm. The thickness of the pressure-sensitive adhesive tape may be, for example, 100, 95, 90, 85, 80, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 50, or 45 μm, or may be within a range between any two of the values ​​exemplified here. Note that the "thickness of the pressure-sensitive adhesive tape" in this specification can be measured by a method conforming to JIS C2107:2011 and can be the average value measured at multiple measurement points (e.g., n = 10 measurement points). The pressure-sensitive adhesive tape according to this embodiment has high substrate strength even at such a thickness. The thickness of the adhesive tape can be measured, for example, using a thickness gauge (manufactured by Mitutoyo Corporation). When the thickness of the adhesive tape is equal to or greater than the lower limit, the base strength of the adhesive tape is further improved. When the thickness of the adhesive tape is equal to or less than the upper limit, the adhesive tape has excellent lightness.

[0013] 1.1 Base material layer The substrate layer according to this embodiment has an uneven surface on the other side (the surface opposite to the surface on which the pressure-sensitive adhesive layer is provided). The uneven surface on the other side is preferably produced by, for example, embossing, as described below. Therefore, the other side according to this embodiment is preferably an uneven surface or an embossed surface. Such surface treatment results in a suitable appearance with less gloss and less noticeable. In this specification, "the surface of the substrate layer has unevenness" means that the arithmetic mean roughness Ra, as described below, of the surface is 0.01 μm or more.

[0014] The arithmetic mean roughness Ra of the other surface of the base layer according to this embodiment is preferably 0.05 to 2.50 μm, more preferably 0.10 to 2.00 μm, even more preferably 0.30 to 1.50 μm, and particularly preferably 0.50 to 1.50 μm. The arithmetic mean roughness Ra of the other surface of the base layer may be, for example, 0.05, 0.10, 0.20, 0.30, 0.40, 0.50, 0.60, 0.70, 0.80, 0.90, 1.00, 1.10, 1.20, 1.30, 1.40, 1.50, 1.60, 1.70, 1.80, 1.90, 2.00, 2.10, 2.20, 2.30, 2.40, or 2.50 μm, or may be within a range between any two of the values ​​exemplified here. The arithmetic mean roughness Ra can be measured, for example, using a surface roughness measuring instrument by scanning a scanning probe over the sample surface under conditions of λc / λs = 2.5 mm / 8 μm and a measurement speed of 0.5 mm / s. If the arithmetic mean roughness Ra of the other surface of the substrate layer is equal to or greater than the lower limit, the surface will have a less glossy, less noticeable, and more desirable appearance. If the arithmetic mean roughness Ra of the other surface of the substrate layer is equal to or less than the upper limit, the substrate strength will be higher, the elongation of the substrate will be improved, and the self-backed adhesive strength of the adhesive tape will be improved.

[0015] The maximum valley depth Rv of the other surface of the base layer according to this embodiment is preferably 0.40 to 12.00 μm, more preferably 0.50 to 10.00 μm, and even more preferably 1.00 to 5.00 μm. The maximum valley depth Rv of the other surface of the base layer may be, for example, 0.40, 0.50, 0.60, 0.70, 0.80, 0.90, 1.00, 1.50, 2.00, 2.50, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50, 6.00, 6.50, 7.00, 7.50, 8.00, 8.50, 9.00, 9.50, 10.00, 10.50, 11.00, 11.50, or 12.00 μm, or may be within a range between any two of the values ​​exemplified here. The maximum valley depth Rv can be measured in the same manner as the arithmetic mean roughness Ra described above. When the maximum valley depth Rv on the other surface of the substrate layer is equal to or greater than the lower limit, the surface has a less glossy and less noticeable appearance, resulting in a more preferable appearance. When the maximum valley depth Rv on the other surface of the substrate layer is equal to or less than the upper limit, the substrate strength is increased, the elongation of the substrate is improved, and the self-backside adhesive strength of the adhesive tape is also improved.

[0016] The arithmetic mean roughness Ra of one surface of the base layer according to this embodiment (the surface on which the pressure-sensitive adhesive layer is provided) is preferably 2.50 μm or less, more preferably 0.10 to 2.00 μm, and even more preferably 0.50 to 1.50 μm. The arithmetic mean roughness Ra of the other surface of the base layer may be, for example, 0.05, 0.10, 0.20, 0.30, 0.40, 0.50, 0.60, 0.70, 0.80, 0.90, 1.00, 1.10, 1.20, 1.30, 1.40, 1.50, 1.60, 1.70, 1.80, 1.90, 2.00, 2.10, 2.20, 2.30, 2.40, or 2.50 μm, or may be within a range between any two of the values ​​exemplified here. When the arithmetic mean roughness Ra of one surface of the substrate layer is equal to or greater than the lower limit, the anchoring property of the pressure-sensitive adhesive layer is improved, and the pressure-sensitive adhesive layer is less likely to peel off.When the arithmetic mean roughness Ra of one surface of the substrate layer is equal to or less than the upper limit, the strength of the substrate is increased, and the elongation of the substrate is improved.

[0017] The thickness of the substrate layer according to this embodiment is preferably 70 μm or less, more preferably 60 μm or less, and even more preferably 55 μm or less. The lower limit of the thickness of the substrate layer according to this embodiment is not particularly limited, but is, for example, 35 μm. The thickness of the substrate layer may be, for example, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 45, 40, or 35 μm, or may be within a range between any two of the values ​​exemplified herein. Note that the "thickness of the substrate layer" in this specification can be measured using a method in accordance with JIS C2107:2011 and can be the average value measured at multiple measurement points (e.g., n = 10 measurement points). The substrate layer according to this embodiment has high substrate strength even at such a thickness. The thickness of the substrate layer may be measured on the substrate layer before the pressure-sensitive adhesive layer is formed, or on the substrate layer from which the pressure-sensitive adhesive layer has been removed using a solvent after the production of the pressure-sensitive adhesive tape. The thickness of the substrate layer can be measured, for example, using a thickness gauge (manufactured by Mitutoyo Corp.) When the thickness of the substrate layer is equal to or less than the upper limit, the pressure-sensitive adhesive tape has excellent lightweight properties.

[0018] In this embodiment, the difference between the maximum and minimum thicknesses of the base layer is preferably within 35% of the thickness of the base layer, more preferably within 30%, and even more preferably within 25%. The lower limit of the difference between the maximum and minimum thicknesses of the base layer is not particularly limited, but is, for example, 2% of the thickness of the base layer. The difference between the maximum and minimum thicknesses of the base layer may be, for example, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, or 2% of the thickness of the base layer, or may be within a range between any two of the values ​​exemplified here. The difference between the maximum and minimum thicknesses of the base layer can be measured, for example, by a method in accordance with JIS C2107:2011, similar to the above-mentioned "thickness of the base layer." It can be the difference between the maximum and minimum values ​​when measured multiple times (e.g., n = 10). When the difference between the maximum and minimum thicknesses of the base layer is equal to or greater than the lower limit, the anchoring property of the adhesive layer is improved, and the adhesive tape is less likely to peel off. When the difference between the maximum and minimum thicknesses of the base layer is equal to or less than the upper limit, workability in applying the adhesive layer is improved, the adhesive can be applied uniformly and thinly, and an adhesive tape with excellent lightness and stable high adhesive strength can be produced. The difference between the maximum and minimum thicknesses of the base layer can be adjusted, for example, in the case of calender molding, by the face length and diameter of the calender roll and the calender roll temperature.

[0019] The base layer according to the present embodiment is preferably composed of a resin composition containing a thermoplastic resin. The resin composition according to the present embodiment may contain, in addition to the thermoplastic resin, for example, a plasticizer, a filler, and other additives.

[0020] 1.1.1 Thermoplastic resin The resin composition according to this embodiment contains a thermoplastic resin. In the resin composition according to this embodiment, the thermoplastic resin is preferably 50% by mass or more, and more preferably 70% by mass or more. In the resin composition according to this embodiment, the thermoplastic resin is preferably 95% by mass or less, and more preferably 80% by mass or less. Examples of the thermoplastic resin according to this embodiment include vinyl chloride resins, ester resins, imide resins, amide resins, and olefin resins. These thermoplastic resins may be used alone or in combination of two or more. The thermoplastic resin according to this embodiment preferably contains a vinyl chloride resin. In this embodiment, the thermoplastic resin preferably contains 80% by mass or more, more preferably 90% by mass or more, of 100% by mass of the thermoplastic resin, and more preferably consists solely of vinyl chloride resin (100% by mass). When such a type of thermoplastic resin is used, the pressure-sensitive adhesive tape has excellent insulation properties and wire binding properties (flexibility, stretchability).

[0021] The vinyl chloride resin according to the present embodiment preferably has an average degree of polymerization of 500 to 2000, more preferably 700 to 1800. The average degree of polymerization of the vinyl chloride resin may be, for example, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, or 2000, or may be within a range between any two of the values ​​exemplified herein. Two or more vinyl chloride resins with different average degrees of polymerization may be used as the vinyl chloride resin according to the present embodiment. When the average degree of polymerization of the vinyl chloride resin is equal to or greater than the lower limit, the polymer chains become entangled, improving the tensile strength of the pressure-sensitive adhesive tape and providing excellent abrasion resistance. When the average degree of polymerization of the vinyl chloride resin is equal to or less than the upper limit, gelation is facilitated, film-forming properties are excellent, and the substrate condition is improved.

[0022] 1.1.2 Plasticizers The resin composition according to this embodiment preferably contains a plasticizer. Examples of the plasticizer according to this embodiment include trimellitate ester-based plasticizers, adipate ester-based plasticizers, phthalate ester-based plasticizers, epoxy-based plasticizers, isophthalate ester-based plasticizers, terephthalate ester-based plasticizers, and phosphoric acid-based plasticizers. These plasticizers may be used alone or in combination of two or more. Preferred plasticizers according to this embodiment include trimellitate ester-based plasticizers, phthalate ester-based plasticizers, and adipate ester-based plasticizers. Using such types of plasticizers enhances the plasticizing effect on the thermoplastic resin and reduces bleed-out.

[0023] The resin composition according to the present embodiment preferably contains more than 28 parts by mass and less than 40 parts by mass of plasticizer per 100 parts by mass of thermoplastic resin. The plasticizer content may be, for example, 28.1, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 39.9 parts by mass per 100 parts by mass of thermoplastic resin, or may be within a range between any two of the values ​​exemplified herein. When the plasticizer content is equal to or greater than the lower limit, the substrate has excellent flexibility, improving workability, reducing the elastic modulus of the pressure-sensitive adhesive tape, and improving the elongation of the substrate. When the plasticizer content is equal to or less than the upper limit, pinhole formation during film formation and stretching is suppressed, resulting in excellent film formability. Furthermore, even a thinned substrate has sufficient elasticity (toughness), improving workability, increasing the elastic modulus of the pressure-sensitive adhesive tape, and increasing the substrate strength. When multiple plasticizers are used in combination, the "plasticizer content" refers to the total amount of the multiple plasticizers.

[0024] 1.1.2.1 Trimellitate ester plasticizers The trimellitic acid ester plasticizer according to this embodiment is preferably a trimellitic acid trialkyl ester (trimellitic acid tri(C4-11 alkyl) ester) represented by formula 1. In formula 1, n is preferably 5 to 10, more preferably 6 to 9, and even more preferably 8. [ka]

[0025] Examples of trimellitic acid tri(C4-11 alkyl) esters according to this embodiment include tributyl trimellitate, trihexyl trimellitate, tri-n-octyl trimellitate, triisooctyl trimellitate, tri-2-ethylhexyl trimellitate, and trinonyl trimellitate. Tri-n-octyl trimellitate is preferred as the trimellitic acid tri(C4-11 alkyl) ester according to this embodiment. When the plasticizer is of this type, the efficiency of plasticizing the thermoplastic resin is high, and the elongation and heat resistance of the substrate are excellent.

[0026] The molecular weight of the trimellitic acid ester according to this embodiment is preferably 378 to 672, more preferably 420 to 630, and even more preferably 462 to 588, for example.

[0027] 1.1.2.2 Phthalate ester plasticizers Examples of phthalate ester plasticizers according to the present embodiment include DINP (diisononyl phthalate), DHP (diheptyl phthalate), DOP (di-2-ethylhexyl phthalate), n-DOP (di-n-octyl phthalate), and diisodecyl phthalate (DIDP). Diesters of phthalic acid and alcohols having 9 to 10 carbon atoms, such as DINP (diisononyl phthalate) and diisodecyl phthalate (DIDP), are preferred as phthalate ester plasticizers according to the present embodiment. Such types of plasticizers provide a high plasticizing effect on vinyl chloride resins, reduce bleedout, and minimize adverse effects on the human body. DINP (diisononyl phthalate) is particularly preferred as the phthalate ester plasticizer according to the present embodiment. Such types of plasticizers provide high plasticizing efficiency.

[0028] 1.1.2.3 Adipate plasticizers Examples of the adipic acid ester plasticizer according to this embodiment include adipic acid-propylene glycol polyester and adipic acid-butylene glycol polyester. Adipic acid polyester is preferred as the adipic acid ester plasticizer according to this embodiment. When the plasticizer is of this type, the substrate has excellent heat resistance.

[0029] 1.1.3 Fillers The resin composition according to the present embodiment may contain a filler. The filler according to the present embodiment is not particularly limited as long as it can easily separate the substrate from the calender roll in the molding step described below.

[0030] The resin composition according to this embodiment preferably contains 10 parts by mass or less of inorganic filler, more preferably 5 parts by mass or less, and even more preferably 1 part by mass or less of inorganic filler, per 100 parts by mass of thermoplastic resin. It is particularly preferred that the resin composition according to this embodiment does not contain an inorganic filler. Examples of inorganic fillers according to this embodiment include calcium carbonate, aluminum hydroxide, magnesium hydroxide, zirconium hydroxide, calcium hydroxide, potassium hydroxide, barium hydroxide, triphenyl phosphite, ammonium polyphosphate, polyphosphate amide, zirconium oxide, magnesium oxide, zinc oxide, titanium oxide, molybdenum oxide, guanidine phosphate, hydrotalcite, smectite, zinc borate, zinc borate anhydrous, zinc metaborate, barium metaborate, antimony oxide, antimony pentoxide, red phosphorus, talc, alumina, silica, boehmite, bentonite, sodium silicate, calcium silicate, calcium sulfate, and magnesium carbonate.

[0031] The resin composition according to this embodiment contains 2 parts by mass or less of calcium carbonate, more preferably 1 part by mass or less, and even more preferably 0.5 parts by mass or less of calcium carbonate, per 100 parts by mass of thermoplastic resin. It is particularly preferred that the resin composition according to this embodiment does not contain calcium carbonate. When the resin composition contains no or no filler, pinholes are less likely to occur during film formation and stretching, resulting in excellent film formability.

[0032] 1.1.4 Other additives The resin composition according to the present embodiment may contain other additives as needed, provided that the effects of the present invention are not impaired. Examples of the other additives include colorants (including pigments such as carbon black), stabilizers, lubricants, antioxidants, and ultraviolet absorbers.

[0033] 1.1.4.1 Stabilizers Examples of the stabilizer according to this embodiment include metal soaps (metal-based composite stabilizers). The inclusion of a stabilizer such as metal soaps facilitates the improvement of the thermal stability of the substrate. Examples of metal-based composite stabilizers include fatty acid calcium, fatty acid zinc, and fatty acid barium. Examples of fatty acid components of metal-based composite stabilizers include lauric acid, stearic acid, and ricinoleic acid. Specific examples of such metal-based composite stabilizers preferably include calcium laurate, calcium stearate, calcium laurate, calcium stearate, calcium ricinoleate, zinc laurate, zinc ricinoleate, zinc stearate, barium laurate, barium stearate, and barium ricinoleate. These may be used alone, or two or more may be used in combination. From the viewpoint that the thermal stability effect is more likely to be enhanced by combining them, a Ca-Zn-based metal stabilizer containing fatty acid calcium and fatty acid zinc is preferably used.

[0034] In one aspect of this embodiment, the proportion of the metal-based composite stabilizer contained in the substrate layer is preferably 0.1 to 10 parts by mass, and more preferably 1 to 5 parts by mass, relative to 100 parts by mass of the thermoplastic resin. In another aspect of this embodiment, the proportion of the metal-based composite stabilizer contained in the substrate layer is preferably 0.5 to 10% by mass, and more preferably 1 to 5% by mass, relative to 100% by mass of the resin composition.

[0035] 1.1.4.2 Lubricants Examples of lubricants according to the present embodiment include higher fatty acids such as stearic acid and palmitic acid; higher alcohols such as palmityl alcohol and stearyl alcohol; metal salts of higher fatty acids such as calcium stearate, zinc stearate, barium stearate, aluminum stearate, magnesium stearate, and sodium palmitate; higher fatty acid esters such as butyl stearate and glyceryl monostearate; and higher fatty acid amides such as oleic acid amide, stearic acid amide, and erucic acid amide. Here, "higher" refers to a carbon number of 9 or more, preferably 9 to 30. These may be used alone or in combination. Among these, stearic acid is preferred from the viewpoint of film-forming properties of the substrate. The content of the lubricant according to the present embodiment is preferably 0.01 to 5.0 parts by mass, more preferably 0.1 to 1.0 part by mass, per 100 parts by mass of the thermoplastic resin.

[0036] 1.2 Adhesive layer The pressure-sensitive adhesive layer according to this embodiment is preferably made of a pressure-sensitive adhesive.

[0037] The thickness of the pressure-sensitive adhesive layer according to this embodiment is preferably 17 μm or less, more preferably 15 μm or less, and even more preferably 13 μm or less. The lower limit of the thickness of the pressure-sensitive adhesive layer according to this embodiment is not particularly limited, but the thickness of the pressure-sensitive adhesive layer is, for example, 3 μm. The thickness of the pressure-sensitive adhesive layer may be, for example, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, or 3 μm, or may be within a range between any two of the values ​​exemplified herein. In this specification, the "thickness of the pressure-sensitive adhesive layer" refers to the difference (absolute value) between the thickness of the pressure-sensitive adhesive tape and the thickness of the base layer. When the thickness of the pressure-sensitive adhesive layer according to this embodiment is within this range, the resulting pressure-sensitive adhesive tape has sufficient adhesive strength while being thin-walled. The thickness of the pressure-sensitive adhesive layer can be measured, for example, by measuring the thickness of the pressure-sensitive adhesive tape according to a method in accordance with JIS C2107:2011 and calculating the difference (absolute value) between the thickness of the pressure-sensitive adhesive tape and the thickness of the base layer measured by the above-mentioned method. The thickness of the pressure-sensitive adhesive layer can be measured, for example, using a thickness gauge (manufactured by Mitutoyo Corporation). When the thickness of the pressure-sensitive adhesive layer is at least the lower limit, the adhesive strength of the pressure-sensitive adhesive tape is improved, and when the thickness of the pressure-sensitive adhesive layer is at most the upper limit, the pressure-sensitive adhesive tape is more lightweight.

[0038] 1.2.1 Adhesive The adhesive according to this embodiment preferably contains a rubber-based adhesive, and is preferably composed of a rubber-based adhesive. The rubber-based adhesive according to this embodiment may be either a melt-type or an emulsion-type. The rubber-based adhesive according to this embodiment preferably contains a base polymer (rubber component) and a tackifier. When the rubber-based adhesive contains such components, it is more likely to exhibit adhesive strength to any adherend.

[0039] 1.2.1.1 Base polymer Examples of base polymers according to the present embodiment include natural rubber, styrene-isoprene-styrene block copolymer (SIS), styrene-butadiene-styrene block copolymer (SBS), hydrogenated products of the above styrene-based block copolymers (SIPS, SEBS), synthetic rubbers such as styrene-butadiene rubber (SBR), polyisoprene rubber (IR), polyisobutylene (PIB), and butyl rubber (IIR), as well as graft copolymers of at least one rubber component selected from (meth)acrylic acid alkyl esters, natural rubber, and the above synthetic rubbers. These base polymers may be used alone or in combination of two or more. The base polymer according to the present embodiment preferably includes a graft copolymer of at least one rubber component selected from (meth)acrylic acid alkyl esters, natural rubber, and the above synthetic rubbers (hereinafter also referred to as "graft rubber"). Using such a base polymer improves the elastic modulus of the pressure-sensitive adhesive layer, suppresses cohesive failure, and improves the self-backed adhesive strength of the pressure-sensitive adhesive tape.

[0040] 1.2.1.2 Tackifiers The tackifier according to the present embodiment can be selected in consideration of the softening point and compatibility with each component. Examples of the tackifier according to the present embodiment include emulsions of terpene resins, rosin resins, hydrogenated rosin resins, coumarone-indene resins, styrene-based resins, petroleum resins, terpene-phenol resins, xylene-based resins, and other aliphatic hydrocarbon resins or aromatic hydrocarbon resins. These tackifiers may be used alone or in combination of two or more.

[0041] 1.3 Other Layers The pressure-sensitive adhesive tape according to the present embodiment may further include other layers within the range that does not impair the effects of the present invention. The pressure-sensitive adhesive tape according to the present embodiment may further include a primer layer between the substrate layer and the pressure-sensitive adhesive layer for the purpose of improving the adhesion between the substrate layer and the pressure-sensitive adhesive layer.

[0042] 1.3.1 Primer layer The primer layer according to this embodiment is preferably made of a composition containing 25 to 300 parts by mass of an acrylonitrile-butadiene copolymer per 100 parts by mass of a graft polymer obtained by graft polymerizing methyl methacrylate onto natural rubber.

[0043] 2. Manufacturing method of adhesive tape The method for producing the pressure-sensitive adhesive tape according to this embodiment includes, for example, a base layer producing step of producing a base layer, and a pressure-sensitive adhesive layer producing step of laminating a pressure-sensitive adhesive on one surface of the base layer.

[0044] 2.1 Base layer fabrication process The substrate layer preparation process according to this embodiment preferably includes, for example, a resin composition preparation process for preparing a resin composition, a molding process for molding the substrate, and a surface processing process for processing the surface of the substrate.

[0045] 2.1.1 Resin composition preparation process The resin composition preparation step according to this embodiment can be carried out by melt-kneading a thermoplastic resin, and, if necessary, a plasticizer, a filler, other additives, etc. The melt-kneading method is not particularly limited, and various mixers and kneaders equipped with a heating device, such as a twin-screw extruder, a continuous or batch kneader, a roll, or a Banbury mixer, are used to mix the resin composition so that it is uniformly dispersed.

[0046] 2.1.2 Molding process The molding step according to this embodiment can be carried out by molding (forming a film) the mixture obtained in the resin composition preparation step using a molding machine. Known molding methods can be used, including, for example, the calendar method, the T-die method, and the inflation method. From the viewpoint of achieving a desired difference between the maximum thickness and the minimum thickness of the substrate layer, the molding according to this embodiment is preferably the calendar method or the T-die method, and particularly preferably calendar molding using a calendar molding machine. Known roll arrangement methods, such as L-type, reverse L-type, and Z-type, can be used in calendar molding.

[0047] 2.1.2.1 Calendar molding process In the calender molding step according to this embodiment, when the face length of the calender roll is L and the diameter is D, the L / D value is preferably 3.5 or less, and more preferably 3.3 or less. The smaller the L / D value, the less deflection of the calender roll there is, and the smaller the difference between the maximum and minimum thicknesses of the base layer can be. Furthermore, the calender roll temperature during calender molding is preferably 160°C or higher, more preferably 165°C or higher, and even more preferably 170°C or higher. When the calender roll temperature is equal to or higher than the lower limit, the viscosity of the resin composition can be reduced, and the thickness of the base layer becomes more uniform.

[0048] 2.1.3 Stretching process The substrate layer preparation process according to this embodiment may further include a stretching process in which the resin composition is stretched. After molding (film formation), the temperature of the resin composition immediately before stretching is preferably 165°C or higher, more preferably 170°C or higher, and even more preferably 175°C or higher. When the temperature of the resin composition immediately before stretching is equal to or higher than the lower limit, the viscosity of the resin composition can be reduced, resulting in a more uniform thickness of the substrate layer. The upper limit of the temperature of the resin composition immediately before stretching is not particularly limited, but can be, for example, 190°C or lower. When the temperature of the resin composition immediately before stretching is equal to or lower than the upper limit, decomposition of the resin can be suppressed. Note that the temperature of the resin composition immediately before stretching refers to, for example, the temperature when, in the case of molding using a calendar molding machine, after film formation with a calendar roll, stretching of the formed resin composition is initiated while peeling it from the calendar roll with a take-off roll (take-off roll).

[0049] 2.1.4 Surface processing process The base layer preparation step according to this embodiment may further include a surface treatment step. The surface treatment step according to this embodiment may be a mirror-finishing step that does not provide irregularities on the surface of the base material, or an embossing step that provides irregularities by embossing, with the embossing step being preferred. The embossing step according to this embodiment preferably involves embossing the other surface of the base material layer (the surface opposite to the surface on which the pressure-sensitive adhesive layer is provided) using an embossing roll. In the embossing step according to this embodiment, for example, the other surface of the base material layer is embossed using an embossing roll so that the arithmetic mean roughness Ra is preferably 0.10 to 2.00 μm, more preferably 0.20 to 1.50 μm, and even more preferably 0.30 to 1.00 μm. In the embossing step according to this embodiment, for example, an embossing roll is used to emboss the other surface of the base layer so that the maximum valley depth Rv is preferably 0.40 to 12.00 μm, more preferably 0.50 to 10.00 μm, and even more preferably 1.00 to 5.00 μm. The arithmetic mean roughness Ra and / or maximum valley depth Rv of the other surface of the base layer can be adjusted by the unevenness of the embossing roll used (specifically, the arithmetic mean roughness Ra and maximum valley depth Rv) and the embossing conditions (for example, pressure and temperature). The embossing conditions include, for example, a processing pressure of 2.0 to 12.0 kg / cm. 2 , preferably 3.0 to 8.0 kg / cm 2 The processing temperature can be set to 150 to 200° C., preferably 160 to 180° C. The unevenness of the embossing roll can be created by, for example, sandblasting, and the arithmetic mean roughness Ra and / or maximum valley depth Rv of the embossing roll can be adjusted by, for example, the abrasive and speed used in sandblasting.

[0050] In the embossing step according to this embodiment, it is preferable to further emboss one surface of the base layer (the surface on which the pressure-sensitive adhesive layer is provided) using a rubber roll. In the embossing step according to this embodiment, for example, the one surface of the base layer is embossed using a rubber roll so that the arithmetic mean roughness Ra is preferably 2.50 μm or less, more preferably 0.10 to 2.00 μm, and even more preferably 0.50 to 1.50 μm. The arithmetic mean roughness Ra of one surface of the base layer can be adjusted by the unevenness of the rubber roll used (specifically, the arithmetic mean roughness Ra and maximum valley depth Rv) and the embossing conditions (for example, pressure and temperature). The embossing conditions include, for example, a processing pressure of 2.0 to 12.0 kg / cm. 2 , preferably 3.0 to 8.0 kg / cm 2 The processing temperature can be 150 to 200°C, preferably 160 to 180°C. In the embossing step according to this embodiment, the base layer is preferably sandwiched between an embossing roll and a rubber roll, and one side and the other side of the base layer are embossed simultaneously. By performing such an embossing step, it is possible to improve production efficiency.

[0051] 2.1.5 Cooling process The substrate layer preparation process according to this embodiment may further include a cooling process. The cooling process according to this embodiment may be performed by cooling the substrate layer after the molding process or the surface processing process. In the cooling process, the substrate temperature may be set to 40°C or less, for example.

[0052] 2.1.6 Trimming process The base layer preparation process according to this embodiment can further include a trimming process. The trimming process according to this embodiment can be performed by cutting both longitudinal ends of the base material. Since thickness variations tend to occur at both longitudinal ends of the base material, the trimming process can reduce the difference between the maximum and minimum thicknesses of the base material layer. Therefore, when forming by the calendering process, it is preferable to make the face length of the calender roll longer than the desired width of the base material layer.

[0053] 2.2 Adhesive layer production process The adhesive layer preparation process according to this embodiment includes, for example, a coating process in which an adhesive is applied to one side of the substrate layer obtained as described above, and a drying process in which the solvent is removed in a drying oven. An adhesive tape can be obtained by this production method. Examples of adhesive application methods include the comma method, lip die method, gravure method, roll method, and slot die method. Furthermore, an adhesive tape of a desired width can be obtained by performing a tape logging process in which the adhesive tape is wound to a desired length around a dried paper tube to form a tape log, and a cutting process in which the obtained tape log is cut to a desired width.

[0054] 2.3 Primer layer preparation process The method for producing a pressure-sensitive adhesive tape according to this embodiment may further include a primer layer preparation step before the adhesive layer preparation step. The primer layer preparation step according to this embodiment includes, for example, a coating step of applying a primer to one surface of the substrate layer obtained as described above, and a drying step of removing the solvent in a drying oven. Examples of primer application methods include gravure, spray, kiss roll, bar, and knife methods. After the primer layer preparation step, an adhesive is applied to the surface of the primer layer, thereby obtaining a pressure-sensitive adhesive tape with improved adhesion between the substrate layer and the adhesive layer.

[0055] 3. Physical properties of adhesive tape 3.1 Adhesion (normal, to SUS) The adhesive strength (normal, to SUS) of the adhesive tape according to this embodiment is preferably 0.5 N / 10 mm or more, and more preferably 0.7 N / 10 mm or more. The adhesive strength (normal, to SUS) of the adhesive tape according to this embodiment is preferably 1.5 N / 10 mm or less. The adhesive strength (normal, to SUS) of the adhesive tape according to this embodiment can be measured, for example, by a method in accordance with JIS C2107:2011 using a SUS plate as the test plate. When the adhesive strength (normal, to SUS) of the adhesive tape is equal to or greater than the lower limit, the adhesive strength is excellent and the adhesive tape can be suitably used in operating mechanical devices or components for mechanical devices. When the adhesive strength (normal, to SUS) of the adhesive tape is equal to or less than the upper limit, the adhesive tape has excellent spreadability and improved workability.

[0056] 3.2 Adhesive strength (normal, against back surface) The adhesive strength (normal, against the back surface) of the adhesive tape according to this embodiment is preferably 0.5 N / 10 mm or more, more preferably 0.7 N / 10 mm or more, and even more preferably 1.0 N / 10 mm or more. The adhesive strength (normal, against the back surface) of the adhesive tape according to this embodiment is preferably 2.0 N / 10 mm or less. The adhesive strength (normal, against the back surface) of this embodiment can be measured, for example, by punching out a portion of the adhesive tape and pressing it against a test plate using a method in accordance with JIS C2107:2011. When the adhesive strength (normal, against the back surface) of the adhesive tape is equal to or greater than the lower limit, the adhesive strength is excellent and the adhesive tape can be suitably used in operating mechanical devices or components for mechanical devices. When the adhesive strength (normal, against the back surface) of the adhesive tape is equal to or less than the upper limit, the adhesive tape has excellent spreadability and improved workability.

[0057] 3.3 Tackiness The tackiness of the adhesive tape according to this embodiment is 1.0 to 4.0 N / 20 mm 2 It is preferable that the resistance is 1.5 to 3.5N / 20mm. 2The tackiness according to this embodiment can be measured by a probe tack test. The probe tack test is carried out, for example, at room temperature of 23±2°C and humidity of 50±2% RH using a probe tack tester ("TE-6001-S" manufactured by Tester Sangyo Co., Ltd.) on a substrate made of SUS and having a contact area of ​​0.25 cm. 2 probe at 100gf / cm for 0.2 seconds 2 The tackiness can be measured by pressing the probe against the adhesive layer of the adhesive tape with a load of 0.01 mm and then measuring the load when the probe is raised at a speed of 10 mm / sec. When the tackiness is at or above the lower limit, the adhesive tape has excellent adhesion to the adherend. When the tackiness is at or below the upper limit, the adhesive tape is easily repositioned, improving workability.

[0058] 3.4 Holding power The holding power of the pressure-sensitive adhesive tape according to this embodiment is preferably 200 min or more, and more preferably 250 min or more. The holding power according to this embodiment can be measured, for example, by a method conforming to JIS Z0237:2009. The greater the holding power, the longer the adhesive strength can be maintained.

[0059] 3.5 Tensile strength The tensile strength of the pressure-sensitive adhesive tape according to this embodiment is preferably 10 N / 10 mm or more, more preferably 11 N / 10 mm or more, even more preferably 13 N / 10 mm or more, and particularly preferably 15 N / 10 mm or more. The tensile strength in this embodiment can be, for example, the tensile strength measured when the pressure-sensitive adhesive tape is subjected to a tensile test according to JIS C2107:2011. The higher the tensile strength, the higher the substrate strength of the pressure-sensitive adhesive tape.

[0060] 3.6 Elongation at break The elongation at break of the pressure-sensitive adhesive tape according to this embodiment is preferably 180% or more, more preferably 190% or more, even more preferably 200% or more, and particularly preferably 210% or more. The elongation at break in this embodiment can be, for example, the strain at break when the pressure-sensitive adhesive tape is subjected to a tensile test according to JIS C2107:2011. The greater the elongation at break, the higher the substrate strength of the pressure-sensitive adhesive tape.

[0061] 3.7 Elastic Modulus The elastic modulus of the pressure-sensitive adhesive tape according to this embodiment is preferably 150.0 to 1000.0 MPa. The elastic modulus of the pressure-sensitive adhesive tape according to this embodiment is preferably 200.0 MPa or more, more preferably 230.0 MPa or more, and even more preferably 250.0 MPa or more. The elastic modulus of the pressure-sensitive adhesive tape according to this embodiment is preferably 750.0 MPa or less, more preferably 700.0 MPa or less, and even more preferably 650.0 MPa or less. The elastic modulus according to this embodiment can be calculated, for example, by the following formula when a tensile test of the pressure-sensitive adhesive tape is performed according to a method in accordance with JIS C2107:2011. (Elastic modulus [MPa]) = {(Tensile stress measured at strain 0.02 [MPa]) - (Tensile stress measured at strain 0.015 [MPa])} / 0.005 When the elastic modulus is equal to or greater than the lower limit, the base strength of the pressure-sensitive adhesive tape is increased, and the wire binding property and workability are improved.When the elastic modulus is equal to or less than the upper limit, the pressure-sensitive adhesive tape has excellent flexibility, and the wire binding property and workability are improved.

[0062] 3.8 Glossiness The glossiness of the other surface of the substrate layer according to this embodiment is preferably 5 to 50, more preferably 10 to 45, and even more preferably 15 to 30. The glossiness of the other surface of the substrate layer may be, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50, or may be within a range between any two of the values ​​exemplified herein. The "glossiness" in this specification may refer to, for example, the 60° gloss value measured by a method conforming to JIS Z8741:1997. The glossiness of the other surface of the substrate layer may be, for example, the average value of values ​​measured at any 10 locations using a gloss meter ("micro-TRI-gloss gloss meter" manufactured by BYK). When the glossiness of the other surface of the substrate layer is equal to or greater than the lower limit, the substrate strength is increased. When the glossiness of the other surface of the substrate layer is equal to or less than the upper limit, a preferable appearance with less gloss and less noticeable appearance is obtained.

[0063] 4. How to use adhesive tape The pressure-sensitive adhesive tape according to the present embodiment can be used for bundling electric wires, specifically for bundling wire harnesses. Accordingly, one embodiment of the present invention is a wire harness having electric wires and an adhesive tape for bundling the electric wires. The pressure-sensitive adhesive tape according to the present embodiment can be used in various mechanical devices, such as automobiles, aircraft, trains, factory automation equipment, home appliances, office automation equipment, medical equipment, communications equipment, and play equipment, or in components for such mechanical devices. Because the pressure-sensitive adhesive tape according to the present embodiment has excellent adhesive strength, it can be particularly suitably used in operational mechanical devices, such as automobiles, aircraft, trains, factory automation equipment, home appliances, and play equipment, or in components for such mechanical devices. [Example]

[0064] The present invention will be described in more detail below with reference to examples. Note that the examples described below are representative examples of the present invention and should not be construed as narrowing the scope of the present invention.

[0065] <Preparation of base layer> Thermoplastic resin, plasticizer, filler, and additives were melt-kneaded in a Banbury mixer to uniformly disperse them, to prepare resin compositions. The formulations of the thermoplastic resin, plasticizer, and filler are shown in Tables 1 to 4. The additives added to each resin composition were 1.5 parts by mass of stabilizer and 0.25 parts by mass of lubricant per 100 parts by mass of thermoplastic resin. Stabilizers: Metallic compound stabilizer: Sakai Chemical Industry Co., Ltd. "OW-5200" Lubricant: Stearic acid: "Sakura Stearic Acid" manufactured by NOF Corporation

[0066] The obtained resin composition was formed into a film and stretched using a calender molding machine to prepare a substrate layer of a predetermined thickness. The L / D value of the calender roll used here was 3.3 or less. The calender roll temperatures during calender molding are also shown in Tables 1 to 4. Furthermore, the substrate layer was sandwiched between an embossing roll having a predetermined arithmetic mean roughness Ra and maximum valley depth Rv (only in Example 6, a mirror-finished roll was used instead of the embossing roll) and a rubber roll having a predetermined arithmetic mean roughness Ra, and an embossing pressure of 5.0 kg / cm was applied. 2 The other surface and one surface of the base layer were simultaneously subjected to uneven processing at a processing temperature of 170°C.

[0067] After the surface treatment, the substrate layer was cooled to 40° C. or less, and then both ends in the length direction were cut.

[0068] <Preparation of adhesive tape> A primer prepared according to the following formulation was gravure coated onto one side of each substrate layer, and the moisture was thoroughly removed in a drying oven to prepare a primer layer. The thickness of the primer layer after drying was 0.3 μm. Next, a pressure-sensitive adhesive prepared according to the formulations in Tables 1 to 4 was applied onto the primer layer using a roll coating, and the moisture was thoroughly removed in a drying oven to prepare a pressure-sensitive adhesive tape. The pressure-sensitive adhesive tapes of the Examples and Comparative Examples prepared in this manner (some of which consisted of only the substrate layer) were subjected to the tests and evaluations described below, and the results are shown in Tables 1 to 4. The thicknesses of the substrate layer, pressure-sensitive adhesive layer, and pressure-sensitive adhesive tape were measured using a thickness gauge (manufactured by Mitutoyo Corporation) according to the method of JIS C2107:2011 (n=10).

[0069] The components used to obtain the resin composition are as follows: Thermoplastic: Vinyl chloride resin 700: Taiyo PVC "TH-700", average degree of polymerization 700 Vinyl chloride resin 1000: Taiyo PVC "TH-1000", average polymerization degree 1000 Vinyl chloride resin 1300: Taiyo PVC "TH-1300", average degree of polymerization 1300 Vinyl chloride resin 1700: Taiyo PVC "TH-1700", average degree of polymerization 1700

[0070] Plasticizer: Phthalate ester plasticizers: "DINP" manufactured by J-Plus Corporation, diisononyl phthalate Trimellitate ester plasticizer: DIC Corporation's "Monocizer (registered trademark) W-750", trioctyl trimellitate Adipate ester plasticizer: Polycizer (registered trademark) W-2050, manufactured by DIC Corporation, polyester adipate

[0071] Filler: Calcium carbonate: "Calcises (registered trademark) P" manufactured by Konoshima Chemical Co., Ltd., calcium carbonate, average particle size 0.18 μm Magnesium hydroxide: "200-06H" manufactured by Kyowa Chemical Industry Co., Ltd., magnesium hydroxide, average particle size 0.54 μm

[0072] The components used to prepare the primer layer were as follows: Primer: E-Tech Co., Ltd.'s "KT4612A" is a mixture emulsion of graft polymer latex, which is made by graft polymerizing natural rubber with methyl methacrylate, and acrylonitrile-butadiene copolymer emulsion.

[0073] The components used in producing the pressure-sensitive adhesive layer are as follows: The formulations shown in Tables 1 to 4 are values ​​calculated as solid content. Base Polymer: Natural rubber: "HA LATEX" manufactured by Resitex Co., Ltd. Styrene-butadiene rubber latex: E-Tech Co., Ltd. "KT-4615B"

[0074] Tackifier: Petroleum resin: Arakawa Chemical Industries, Ltd. "AP-1100"

[0075] <Film forming properties> The resin composition was evaluated for the presence or absence of pinholes when stretched. (Pinhole) The state of the substrate when the resin composition was stretched was visually evaluated according to the following criteria. A: No pinholes were found B: Pinholes were found, but there were 1 to 5 in a 5cm x 5cm area. C: Pinholes were confirmed, with 6 or more in a 5cm x 5cm area

[0076] <Maximum and minimum thickness of base layer> The thickness of the base material layer was measured (n=10) using a thickness gauge (manufactured by Mitutoyo Corporation) according to a method in accordance with JIS C2107:2011, and the maximum and minimum values ​​were recorded. (difference between maximum and minimum thickness of base layer) The difference between the maximum and minimum values ​​of the substrate layer obtained in the above measurement was calculated.

[0077] <Surface analysis test> The substrate was cut to a size of 50 mm x 20 mm to obtain a sample. An acrylic plate (100 mm x 300 mm) was placed on a flat surface with the measurement surface of the sample facing upward. A small surface roughness measuring instrument (Mitutoyo Corporation, "Surftest (registered trademark) SJ-210") and its scanning probe were placed on the sample so that they were parallel to the sample flow direction. Measurements were performed by scanning the scanning probe over the sample surface under conditions of λc / λs = 2.5 mm / 8 μm and a measurement speed of 0.5 mm / s. (arithmetic mean roughness Ra) The arithmetic mean roughness Ra was calculated from the measurement results obtained in the above-mentioned surface analysis test. (Maximum valley depth Rv) The maximum valley depth Rv was calculated from the measurement results obtained in the above-mentioned surface analysis test.

[0078] <Adhesion test> (Adhesion strength (normal, against SUS)) Using a SUS plate as a test plate, the adhesive strength of the adhesive tape was measured according to a method conforming to JIS C2107: 2011. For the measurement, a tabletop precision universal testing machine ("Autograph (registered trademark) AGS-1kNX" manufactured by Shimadzu Corporation) was used. (Adhesive strength (normal, against back surface)) A portion of the adhesive tape was punched out and pressure-bonded to a test plate, and the adhesive strength of the adhesive tape was measured according to a method in accordance with JIS C2107: 2011. For the measurement, a tabletop precision universal testing machine ("Autograph (registered trademark) AGS-1kNX" manufactured by Shimadzu Corporation) was used.

[0079] <Probe tack test> Test was performed using a probe tack tester (TE-6001-S manufactured by Tester Sangyo Co., Ltd.) at a room temperature of 23±2°C and a humidity of 50±2%RH. The material was SUS, and the contact area was 0.25cm. 2 probe at 100gf / cm for 0.2 seconds 2 The probe was pressed against the adhesive layer of the adhesive tape with a load of 0.01 mm, and the load was measured when the probe was raised at a speed of 10 mm / sec (n=10). (tackiness) The average value of the measurement results obtained in the above-mentioned probe tack test was calculated.

[0080] <Retention force test> (holding force) Measurement was performed using a method conforming to JIS Z 0237:2009. Specifically, a 19 mm wide, 100 mm long adhesive tape was left standing for at least 24 hours in an environment with a temperature of 23±2°C and a humidity of 50±5%RH, and then a portion of the adhesive tape (25 mm long) was attached to a glass plate. A 500 g weight chuck was then attached to the side of the adhesive tape opposite the portion attached to the glass plate, and the weight was placed on a stand so that the weight was not applied. After preheating for 20 minutes in an atmosphere of 40°C, the stand was lowered to apply the 500 g weight to the adhesive tape, and the elapsed time until the tape peeled off and fell from the glass plate was measured.

[0081] <Tensile test> A tensile test of the adhesive tape was carried out according to a method conforming to JIS C2107: 2011. Specifically, using a tabletop precision universal testing machine (Shimadzu Corporation's "Autograph (registered trademark) AGS-1kNX") in an environment of 23±2°C temperature and 50±5% RH, an adhesive tape 19 mm wide and 200 mm long was attached to a chuck with a gripping interval of 100 mm so that a load was applied uniformly in the width direction, and measurement was carried out at a tensile speed of 300 mm / min, and the average value of five measured values ​​was recorded. (tensile strength) The tensile strength was calculated from the measurement results obtained in the above-mentioned tensile test. (elongation at break) The elongation at break was calculated from the measurement results obtained in the above-mentioned tensile test. (elastic modulus) From the measurement results obtained in the above tensile test, the elastic modulus was calculated using the following formula. (Elastic modulus [MPa]) = {(Tensile stress measured at strain 0.02 [MPa]) - (Tensile stress measured at strain 0.015 [MPa])} / 0.005

[0082] <Flexibility test> Ten heat-resistant automotive wires ("AVX050", manufactured by Sumitomo Wiring Systems, Ltd., diameter: 50 mm) cut to lengths of 800 mm and four heat-resistant automotive wires ("AVX085", manufactured by Sumitomo Wiring Systems, Ltd., diameter: 85 mm) cut to lengths of 800 mm were prepared. These 14 wires were bundled together, and both longitudinal ends were secured together with adhesive tape to facilitate winding. Then, the adhesive tape (width: 19 mm) of each Example or Comparative Example was wrapped around the wires in a half-wrap to prepare a sample for evaluation. Here, "half-wrap winding" refers to wrapping the adhesive tape around the wire so that half of the width of the adhesive tape overlaps half of the width of the adhesive tape already wrapped around it. (Easy to wrap around electric wire) The evaluation samples prepared in the above test were evaluated for the occurrence of wrinkles, lifting, and peeling.

[0083] <Weighing test> The adhesive tape was weighed and the mass per unit area was calculated. (Lightweight) The mass per unit area obtained in the weighing test was evaluated according to the following criteria. A:80g / m 2 less than B:80g / m 2 End

[0084] <Gloss test> The gloss of the surface of the substrate was measured at 10 arbitrary points on the other surface of the substrate using a micro-TRI-gloss gloss meter (manufactured by BYK). (glossiness) The average value of the gloss values ​​obtained in the above gloss test was calculated.

[0085] <Appearance test> The appearance of one surface of the substrate of the pressure-sensitive adhesive tape was visually evaluated. (exterior) The appearance of one surface of the substrate was evaluated according to the following criteria. A: Almost no gloss and barely noticeable B: Glossy

[0086] Table 1

[0087] Table 2

[0088] Table 3

[0089] Table 4

Claims

1. a base layer made of a resin composition containing a thermoplastic resin; a pressure-sensitive adhesive layer provided on one surface of the base layer; An adhesive tape comprising: the resin composition contains 2 parts by mass or less of calcium carbonate and more than 28 parts by mass and less than 40 parts by mass of a plasticizer relative to 100 parts by mass of the thermoplastic resin; An adhesive tape, wherein the other surface of the base layer has projections and recesses.

2. The pressure-sensitive adhesive tape according to claim 1 , wherein the difference between the maximum thickness and the minimum thickness of the base layer is within 30% of the thickness of the base layer.

3. The pressure-sensitive adhesive tape according to claim 1, wherein the other surface has an arithmetic mean roughness Ra of 0.10 to 2.00 μm.

4. The adhesive tape according to claim 1 , wherein the thickness of the adhesive tape is 75 μm or less.

5. The pressure-sensitive adhesive tape according to claim 1 , wherein the pressure-sensitive adhesive layer has a thickness of 15 μm or less.

6. The pressure-sensitive adhesive tape according to claim 1 , wherein the resin composition does not contain an inorganic filler.

7. The pressure-sensitive adhesive tape according to claim 1 , wherein the thermoplastic resin comprises a vinyl chloride resin.

8. The pressure-sensitive adhesive tape according to any one of claims 1 to 7, which is used for bundling electric wires.

9. A wire harness comprising: electric wires; and the adhesive tape according to claim 8 for bundling the electric wires.

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